English is doable IMO, there are so many accents already that you should be able to find one that suits you (except you must be able to say "r") if you just have to get rid of your accent.

Now try swedish. Just impossible.

I don’t think it’s impossible to do, just impossible to do alone. If you’ve got enough time and a good dialect coach, you can totally get there (H>E at least, I’d suspect E>H is harder for many reasons)

I mean kinda cheating but im bilingual but i still fail. I have an english accent when speaking hungarian and a hungarian accent when speaking english. Also words i dont use often come out in an irish accent cause i grew up there. Language is fluid in my head rather than something concrete. At this point im even mixing swedish words into it even tho i dont speak much of it.

There is a known phenomena among some E Asian living in America to learn English so thoroughly that they loose the accent. The problem is that their English is too good; their diction becomes the accent that gives them away.

It's almost impossible to pass as a native speaker without years of immersion in the culture.

Challenge accepted. My English is flawless