So, I noticed something while looking for references for a possible griffon character. It’s common knowledge that while ponies use the same body shape (baring a few exceptions), there are noticeable differences between genders, namely muzzle shape and eyelashes/lack there of. Thing is that these differences apply to griffons as well.

As of the end of Season 4, a total of five griffons have appeared on screen. The first was obviously Gilda in “Griffon the Brush Off”,

The second was Gustave Le Grand from “MMMystery On The Friendship Express”. Even though this introduced a griffon of both genders, two is not an adequate sample size to make any comparison for the griffon species as a whole.

Then Rainbow Falls aired, which included not one, not two, but three griffons (one male and two females) present in the background of several scenes.

Between three females and two males, certain patterns started to appear.

• A griffon’s fur coat, feathers and talons/beak are all different colors.
  
• Talons and beaks are always the same color.
  
• The tuft at the end of a griffon’s tail is always the same color as their wings.
  

Presumably, these characteristics are present in every member of the Griffon species, though there are rare exceptions.

• Both Gilda and one of the female griffons have white head feathers as opposed to their wing feathers. This means that griffons can have two different colored feathers, something I can’t say the same to in regards to Pegasus.***
  
• One of the female griffons has black talons/beak, but also black feathers. However, she still has at least three different colors overall.
  
• Three of the five griffons have yellow talons, marking that as the most common color, though other colors do exist.
  

With that out of the way, let’s talk about gender differences in regards to ponies. Baring ponies with unique character models like Big Macintosh and Fleur, there are three distinct differences between genders that can be noticed at a glance:

• A different muzzle shape, rounded for mares and more boxy for stallions
  
• Mares have eyelashes, while stallions do not.
  
• Some stallions have unshaven fetlocks the same color as their manes, namely Fancy Pants, Shining Armor and Big Macintosh.
  

What I found is that two of these distinctions also apply to griffons. Male griffons have noticeably larger and wider beaks compared to females, similar to how different species of birds have different beak shapes and sizes.

Secondly, notice that Gilda's most distinct feature is a “wing-shaped” marking around her eyes, also seen on the two female griffons from Rainbow Falls. This marking is always a different color to their head feathers, either a secondary feather color or the same color as their talons/beak.

Comparably, this could be considered a griffon’s “eyelashes” and as such male griffons do not naturally have these markings around their eyes. Why am I even bringing all this up? Well, because I’m still finding griffon designs that have these markings regardless of gender. It was understandable at first because most used Gilda’s model as a base, but now it’s about as weird as if a stallion had eyelashes and I'm just pedantic about those sort of details.

***BONUS RANT!