As to not make the previous post too long I decided to put all of the details regarding special changeling types into their own post. Most players playing a changeling will play a standard changeling, but might know about these special types and use them as secondary or background characters.

Note that I don't consider most of the Other types cannon in my own works, but I have encountered them on the forums so I'll provide information on them, and recommend more lore-friendly alternatives.

Queens

Changeling Queens are quite well known and mostly understood already. As stated in the previous post, Queens are the primary method whereby new changelings are made, as such they are often the leader of the hive, and biologically they are far more robust and powerful than a standard changeling. Chrysalis being able to beat Celestia in a 1v1 was not a fluke, Changeling Queens, when properly healthy and energized, are equal in raw magical power to alicorns. This is due to their innately stronger connection to the magical field, due to them primarily being magical entities. 

Despite this level of power, Queens are still vulnerable to physical assault. Like standard changelings, they will burn if their magical field is dispelled and they are not nearly so physically strong as an alicorn, Even a well trained Earth Pony could beat a Changeling Queen in hoof to hoof combat. So the Queen will rarely leave the hive and will prefer to do all fighting magically and from a distance, utilizing personal guards to maintain separation from combatants whenever possible.

Similar to Alicorns, Changeling Queens are also remarkably long lived, the youngest queen, before the introduction of Oracle and Maripose (Of my own design) was several centuries old with the average age for a queen being a full 1000 years. Queens are biologically immortal, in that they do not die of old age, but they are prone to various dangerous mental deteriorations once they get too old. Queen Geletine, whose hive turned to bloodlust after a betrayal is an example of this, while Queen Nirvana, the oldest known Queen, has managed 3000 years without any sign of deterioration, which she credits to her time spent among the Himallaman monks and her hive's focus on inner peace and her namesake.

Queens are formed in a similar process to standard changelings, albeit much more resource intensive. While a standard changeling only takes a few months to gestate in the cocoon, a Changeling Queen takes a full year at the shortest, and up to two years at most before they are ready to leave the cocoon. They also take longer to fully mature than a standard changeling. Instead of being ready to enter the world at 3 years old, a Queen will not be considered ready to leave until 7 years, and not fully matured until 12.

While this is still quite fast compared to pony development times, this is a significant increase compared to standard changelings. Finally, while standard changelings can be made in batches, Queens can only be made individually. Queen Geletine, during her psychosis, tried to make two queens at once, and the result was Queen Sleipnir, who despite having double the number of appendages was still just one Queen.

In the rare event that the Queen dies, traditionally the remaining changelings would be adopted by other nearby hives or simply do their best to keep moving in the absence of their queen, often deluding themselves into believing that their queen is not dead, but rather trapped or otherwise incapacitated. There is however a way for a hive to make a new queen, called an Ascended Queen, utilizing one of their own standard changelings and putting them through a similar process to how a normal Queen is made. The changeling selected for ascension is sealed in a cocoon filled with emotion gel, and the gel is charged with all available types of emotional energy. After a full year of constant charging the new queen will emerge, but their personality will be altered slightly depending on the emotional mix and who was doing the energizing. Thus it is important to either ensure that the mix is as even as possible and the chargers are rotated evenly, or that the mix is predominantly the same as the hive's original mix, and that the chargers are exclusively from the same cocoon as the one being ascended in order to minimize alterations to the new Queen's personality.

This is a risky method to gain a queen, and as such is only performed in dire circumstances.

Kings

A Changeling King is a special type of Pony/Changeling hybrid created via the same method as ascending a changeling to a Queen. However, changeling Kings have more in common with Reformed Changelings than standard, as they retain a biological gender (In that they are still capable of producing equine offspring in whichever manner they were capable of before the transformation), do not require emotional energy to survive, and will not burn when killed. Kings are about halfway between a changeling and a Queen in terms of strength and size.

In my experience, Kings only appear when a Queen is in love with a pony, which very rarely happens, due to the cost of forming one being equal to making a new queen, Kings are seen more as an indication that a hive is doing exceptionally well.

In my stories, only 3 changeling Kings were ever made. Rasputin Stalliongrad with Queen Geletine, who betrayed her. Trojan Horse with Queen Permutation, who was murdered as part of a coup in Troy. And, in some timelines, Daxter Blackwater with Queen Oracle.

Other

Partially Converted Ponies

This is a common one in fan-fiction, a pony is captured by changelings and converted into a changeling by force. I don't like this concept as it's less efficient than making new changelings the normal way, more often than not produces inferior changelings who are not keen on helping the hive, and often the conversion just fails and the pony dies either during the process, or soon after when their magic fails.

You could say that an insane hive, either due to an insane queen or one who lost their queen, might try this to bolster their numbers.

Pony/Changeling Hybrid

This stems from the fandom's obsession with hybrid everything. Just pick a species and stick with it! You'll find better ways to make your character unique than just making them a new hybrid type.

Further, as changelings are infertile in my fanon, they simply can't be made, at least with standard changelings. The presence of Reformed Changelings makes this subset possible and practical with either parental configuration, and the abilities of the hybrid will be the same or similar to a reformed changeling.

If there are other types that I've missed, please let me know so I can add them, or if anything is unclear I'd be happy to expand this like all other posts.