Do you recommend watching the entire source of your canon before confirming/entertaining the possibility of a kintype? I have a memory of working with something like an elecmon but I don’t think that matches anyone in the anime anyway. But I don’t want to talk about what I remember and have anyone tell me it’s impossible because of something I haven’t seen? Maybe I should watch it to fact check?

Watch as much as is useful to you. No one can ‘fact check’ you and say your kintype can’t have done something just because it didn’t…

Regarding “xenomnesia”: It’s possible you have a mental connection with a character. Or empathic. Some kind of connection that let you share thoughts or memories. Or maybe even: Is there any kind of otherkin “vessel” concept in use? Channeling someone? Or having them give you thoughts/memories somehow? (I’m an empath, and I know a lot of my synpath [non-kin, but very deeply understanding] connections have this effect on me, especially my primary “soulbond”.)

Absolutely. There’s lots of reasons that this phenomenon could occur. Fictionflickers come to mind too as a possible source for xenomnesia.