One of the fun things to play with on cross-species mutations (transfers) and the impact on identity or community is… what would the characters even know? If they have access to the original species, what would that access be limited to? How much effort would this or that character put into learning about their transfer species, be it physically or otherwise?
In A Beneficial Union, the main transfer is from the Vulpin sophont species (whom are referred to as “Vulps” and whose languages don't have a verbal or auditory equivalent, adding an extra barrier). Vulps have five main species with some crossbreeding. I wanted to stick to some of Ben 10 wonk logic and to keep Earth distinctly unique (Earthlings can adapt and travel with accommodations), so species are largely geographically based. The practice of memory transfers and intercity pheromone usage ensures a sense of global community, they do not war with one another.
^^These are Vulp workers, the counterparts being drones and matriarchs. It's a bit out of date, but workers look very nearly related, you can tell they're all from the same genus.
This is an unfinished Midlander drone, whom I designed to try and make it more realistic for a human with additive features to pass for. (Translation: Slap a tail on Ben and he looks like a deformed, bald drone with chronic bipedalism).
Suffice it to say, what a character will perceive of their transfer species will vary greatly on their exposure. Most would never meet or hear about the fifth species per the greater distance and overall lack of traveling, the other four all have booming trade systems and some nomadic cultures within them.
So the thing I was wondering is would a character even realize that Vulps have ethnicities rather than just species? Would they spot a Midlander with maybe a more curved barb and sharper stripes and think them, not a different phenotype as we see in cat litters, but a people all of their own?
(I kinda hope not because I am not ready to design and write all those different cultures. /j)