I noticed something and that's common for german translations, that the german episode title is often not a 1:1 translation, but sometimes even completly different. I translate those back to english

Season 1
1.Friendship is Magic, Part 1 = Ein Auftrag von Prinzessin Celestia, Teil 1 = A task From Princess Celestia, Part 1
2.Friendship is Magic, Part 2 = Ein Auftrag von Prinzessin Celestia, Teil 2 = A Task From Princess Celestia, Part 2
3.The Ticket Master = Eine Freundin hat's nicht leicht = A Friend Doesn't Has It Easy
4.Applebuck Season = Apfelschüttelernte = Applebuck Harvest
5.Griffon the Brush Off = Gilda, die Partybremse = Gilda, the Party Pooper
6.Boast Busters = Angeber-Trixie = Show-Off Trixie
7.Dragonshy = Drachenscheu = Dragonshy
8.Look Before You Sleep = Die Pyjama-Party = The Pyjama-Party
9.Bridle Gossip = Das fremde Zebra = The Strange Zebra
10.Swarm of the Century = Fürchterlich niedliche Tierchen = Awful Cute Animals
11.Winter Wrap Up = Frühlingsanfang in Ponyville = Early Spring in Ponyville
12.Call of the Cutie = Etwas ganz Besonderes = Something Really Special
13.Fall Weather Friends = Das Blätterrennen = The Leaves Race(Or Running of the Leaves fits too)
14.Suited for Success = Die Modeschau = The Fashion Show
15.Feeling Pinkie Keen = Pinkie-Weisheiten = Pinkie Wisdoms
16.Sonic Rainboom = Rainbows Großer Tag = Rainbow's Big Day
17.Stare Master = Babysitter Fluttershy = Babysitter Fluttershy
18.The Show Stoppers = Die Showstars = The Show Stars
19.A Dog and Pony Show = Diamanten-Hunde = Diamond Dogs
20.Green Isn't Your Color = Fluttershy auf dem Laufsteg = Fluttershy on the Catwalk
21.Over a Barrel = Büffelherden und Apfelbäume = Buffalo Herds and Apple Trees
22.A Bird in the Hoof = Celestias Haustier = Celestia's Pet
23.The Cutie Mark Chronicles = Schönheitsflecken-Geschichten = Cutie Mark Stories
24.Owl's Well That End's Well = Eule gut, alles gut = Owl good, all good
25.Party of One = Im Partyfieber = In Party Fever
26.The Best Night Ever = Die große Galloping-Gala = The Grand Galloping Gala

Season 2
1.The Return of Harmony Part 1 = Freundschaft über alles, Teil 1 = Friendship Over Everything, Part 1
2.The Return of Harmony Part 2 = Freundschaft über alles, Teil 2 = Friendship Over Everything, Part 2
3.Lesson Zero = Twilight flippt aus = Twilight Freaks Out
4.Luna Eclipsed = Lunas Verwandlung = Luna's Change
5.Sisterhooves Social = Das Hufschwestern Festival = The Sisterhooves festival
6.The Cutie Pox = Viel zu viele Schönheitsflecken = Way Too Many Cutie Marks
7.May The Best Pet Win! = Ein Lieblingstier für Rainbow Dash = A Favourite Animal For Rainbow Dash
8.The Mysterious Mare Do Well = Rainbow Dash, die Retterin = Rainbow Dash, The Saviour
9.Sweet and Elite = Rarity will dazu gehören = Rarity Wants To Be A Part Of It
10.Secret of My Excess = Spike wird raffgierig = Spike Get's Greedy
11.Hearth's Warming Eve = Großes Theater! = Great Theater!
12.Family Appreciation Day = Die Geschichte von Ponyville = The Story of Ponyville
13.Baby Cakes = Pony-Nachwuchs = Pony-Offspring
14.The Last Roundup = Das letzte Rodeo = The Last Rodeo
15.The Super Speedy Cider Squeezy 6000 = Apfelsaft für alle Ponys = Applejuice for Everypony
16.Read It and Weep = Rainbow Dash, die Leseratte = Rainbow Dash, The Bookworm
17.Hearts and Hooves Day = Herz- und Huf-Tag = Hearts and Hooves Day
18.A Friend in Deed = Ein ganz besonderer Freund = A Really Special Friend
19.Putting Your Hoof Down = Fluttershy setzt sich durch = Fluttershy Pushes Trough
20.It's About Time = Zeitreisen = Time Travel
21.Dragon Quest = Spike, das Drachenpony = Spike, The Dragonpony
22.Hurricane Fluttershy = Fluttershy und die Fliegerei = Fluttershy and the Flying
23.Ponyville Confidentional = Gabby Gums macht Geschichte = Gabby Gums Makes History
24.MMMystery on the Friendship Express = Pinkie und Twilight ermitteln = Pinkie and Twilight Investigates
25.A Canterlot Wedding, Part 1 = Hochzeit in Canterlot, Teil 1 = Wedding in Canterlot, Part 1
26.A Canterlot Wedding, Part 2 = Hochzeit in Canterlot, Teil 2 = Wedding in Canterlot, Part 2

Season 3
1.The Crystal Empire - Part 1 = Das Kristall-Königreich, Teil 1 = The Crystal Empire, Part 1
2.The Crystal Empire - Part 2 = Das Kristall-Königreich, Teil 2 = The Crystal Empire, Part 2
3.Too Many Pinkie Pies = Zu viele Pinkie Pies = Too Many Pinkie Pies
4.One Bad Apple = Besuch aus Mähnhattan = Visit From Manehattan
5.Magic Duel = Das Einhorn-Amulett = The Unicorn Amulet
6.Sleepless in Ponyville = Schlaflos in Ponyville = Sleepless in Ponyville
7.Wonderbolts Academy = Nicht um jeden Preis = Not at All Costs
8.Apple Family Reunion = Das Familienfest der Apples = The Apple Family Celebration
9.Spike at Your Service = Spike zu Diensten = Spike at Your Service
10.Keep Calm and Flutter On = Discord wird ein guter Drache = Discord Becomes A Good Dragon
11.Just for Sidekicks = Juwelenkuchen und Haustiere = Gemcake and Pets
12.Games Ponies Play = Die Equestria-Spiele = The Equestrian Games
13.Magical Mystery Cure = Prinzessin Twilight = Princess Twilight

Season 4
1.Princess Twilight Sparkle - Part 1 = Prinzessin Twilight Sparkle - Teil 1 = Princess Twilight Sparkle - Part 1
2.Princess Twilight Sparkle - Part 2 = Prinzessin Twilight Sparkle - Teil 2 = Princess Twilight Sparkle - Part 2
3.Castle Mane-ia = Ponygrusel in Schloss = Ponyhorror in the Castle
4.Daring Don't = Wo bleibt Daring? = Where Is Daring?
5.Flight to the Finish = Kampf bis zum Ende = Fighting Until The End
6.Power Ponies = Power-Ponys = Power Ponies
7.Bats! = Flutterflughund = Flutter Flying Dog
8.Rarity Takes Manehattan = Rarity in Mähnhattan = Rarity in Manehattan
9.Pinkie Apple Pie = Pinkie Apple Pie = Pinkie Apple Pie
10.Rainbow Falls = Rainbow kommt zur Vernunft = Rainbow Comes To Her Senses
11.Three's A Crowd = Drei ist Einer zu viel = Three Are One Too Much
12.Pinkie Pride = Pinkies Stolz = Pinkie's Pride
13.Simple Ways = Das einfache Leben = The Simple Life
14.Filli Vanilli = Flutter-Vanilli = Flutter Vanilli
15.Twilight Time = Twilight-Zeit = Twilight Time
16.It Ain't Easy Being Breezie = Nicht einfach, ein Breezie zu sein = Not Easy Being a Breezie
17.Somepony To Watch Over Me = Das Aufpasser-Pony = The Keeper-Pony
18.Maud Pie = Maud Pie = Maud Pie
19.For Whom The Sweetie Belle Toils = Sweetie Belle in Aktion = Sweetie Belle in Action
20.Leap of Faith = Der magische Flim-Flam-Trank = The Magical Flim-Flam-Potion
21.Testing, Testing, 1, 2, 3 = Die Geschichte der Wonderbolts = The History of The Wonderbolts
22.Trade Ya! = Die Handelsmesse = The Trade Fair
23.Inspiration Manifestation = Inspirations-Manifestation = Inspiration Manifestation
24.Equestria Games = Die Equestria Spiele = The Equestria Games
25.Twilight's Kingdom - Part 1 = Twilights Königreich, Teil 1 = Twilight's Kingdom, Part 1
26.Twilight's Kingdom - Part 2 = Twilights Königreich, Teil 2 = Twilight's Kingdom, Part 2

Season 5
1.The Cutie Map - Part 1 = Die Landkarte - Teil 1 = The Map - Part 1
2.The Cutie Map - Part 2 = Die Landkarte - Teil 2 = The Map - Part 2
3.Castle Sweet Castle = Zuhause ist es am Schönsten = Home Sweet Home
4.Bloom & Gloom = Träume und Alpträume = Dreams and Nightmares
5.Tanks for the Memories = Abschied von Schildi = Farewell for Schildi
6.Appleoosa's Most Wanted = Gesucht: Trouble Shoes = Wanted: Trouble Shoes
7.Make New Friends but Keep Discord = Neue Freunde mit Discords Erlaubnis = New Friends With Discord's Approval
8.The Lost Treasure of Griffonstone = Der Schatz von Greifenstein = The Treasure of Griffonstone
9.Slice of Life = Lebensentscheidunen = Life Decisions
10.Princess Spike = Prinzessin Spike = Princess Spike
11.Party Pooped = Partystress = Party Stress
12.Amending Fences = Alte Freundschaften = Old Friendships
13.Do Princesses Dream of Magic Sheep? = Träum Prinzessinen von Schäfchen? = Do Princesses Dream of Sheeps?
14.Canterlot Boutique = Das Canterlot-Karussell = The Canterlot-Carousel
15.Rarity Investigates! = Raritys Ermittlungen = Rarity's Investigations
16.Made in Manehattan = Auftrag in Mähnhattan = Job in Manehattan
17.Brotherhooves Social = Das Hufbruder-Festival = The Brotherhoof festival
18.Crusaders of the Lost Mark = Der Schönheitsfleck = The Cutie Mark
19.The One Where Pinkie Pie Knows = Pinkies Geheimnis = Pinkie's Secret
20.Hearthbrakers = Das Familienfest = The Family Fest
21.Scare Master = Gruselige Fluttershy = Creepy Fluttershy
22.What About Discord? = Spaß mit Discord = Fun With Discord
23.The Hooffields and McColts = Die Hooffields und die McColts = The Hooffields and The McColts
24.The Mane Attraction = Die Hauptattraktion = The Main Attraction
25.The Cutie Re-Mark – Part 1 = Das Schönheitsflecken-Duell – Teil 1 = The Cutie Mark Duel - Part 1
26.The Cutie Re-Mark – Part 2 = Das Schönheitsflecken-Duell – Teil 2 = The Cutie Mark Duel - Part 2

Season 6
-No german episode name yet