>>530955016
you are correct. the xenogerm will replace all xenogenes. it will overwrite endogenes in the case of eye, hair or skin color. you cannot add genes later.
also, when you install the xenogerm, you will get a very long cooldown of more than a year before you can harvest or install another xenogerm without killing the colonist. therefore you should only implant a xenogerm when you've very happy with it, unless you're willing to wait a very long time to replace it.

female pawn