I can't help you with assets since I don't know how to edit, but being south-american (im argentinian), I can help with information.Well, I see the point, but I never really understood the reason to force people to exit the game, change folders, open the game again just if you want to switch e.g. from WC 1998 to WC 2002.
I still think the more teams we can fit, the better.
And when we reach the limit and need space, then we can start removing the oldest teams from that DB
But I see that a "clean" 2020s DB might also be useful.
Regarding Copa America, I've considered this possibility, especially given that valambrosio and ovide have done them for post 10s addon before, it would make sense to port them over.
On the other hand, @valambrosio2 also mentioned that he would be transfering Euro 2020 and WC 2022 to his project, so idk if we do double work there.
Also as far as I know there are still a few stadiums missing from the latest iterations?
To be honest I am clueless about South American football, and would definitely need help, including with graphics, if any are missing.
Same goes for Copa Libertadores (finalists) - sounds fun but I have zero content or knoknowledge.
At the moment of this message, although it is for FIFA 23, a group of Ecuadorian editors are releasing a patch for Latin American football. (This is the link for their social media https://biolink.website/EcuadorModders)
Besides that, although my eyes opened with joy when I read one year south American teams, I would understand the 5 year team approach. Right know, our continent is dominated by Brazilian clubs since they are the only ones that can afford quality players. After that, you have a lot of argentinian clubs, and then rarely you have teams from other countries that can make a difference.