I'm going to be a little harsher than I tend to be so I hope this doesn't come off as rude.
Can you? probably.
But;
it feels like identifying as someones fursona. Even though it's not the person behind the character, the character is still intended as a personal facet of that person. If someone told me they think they're kin with any of my OCs, that'd be neat. But if someone told me they were otherkin with my fursona I think I'd break all my baseline pleasantries and tell them that, "no", they weren't, because the character exists solely as a personal reflection of myself. I may not be my fun little cartoon character I enjoy drawing, but that same cartoon character is me. It is intended to be viewed...