It works for soccer. I'm just saying that eventually (ie 50-100 years or more) this might be plausible.
But I think it works well in soccer because there are multiple high-level leagues across the globe - where for baseball the MLB is the
highest level of competition globally. That doesn't outright stop trades of course, teams of unequal competition will trade with each other for mutual benefit, but I don't think that many of the players that play in the MLB would really be happy if they were traded to Japan in a trade. Not all of them, but most of them.
Now if our cultures were a bit closer than I'd probably make an argument for it but from what I have read transitioning to life in Japan as an American baseball player can be extremely difficult and lonely. I would imagine that the transition for Japanese players coming to the US is just as difficult. Probably even more tough for players who have families. So there's a personal aspect that'll be tough on the traded player.
When baseball develops good, global competition - which I don't see happening anytime soon - then trading globally will be great. Until then, no.