America have sort of done this in the rugby 7s for the Olympics. A lot of players have crossed over from NFL and sprinting. I think they are now a medal contender.
It’s all about talent ID and transferable skills.
Handball must be a more unique sport though. Rugby 7s is a pretty simple game with more space available. That makes it less tactical.
I don’t know enough about handball to comment much but there must be a reason. They must have tried talent ID for better athletes if they are already doing it in rugby. Feels like the competition League formats in Europe have a big effect and have evolved the game. Must make it tougher to break into.
Interestingly Jay Cutler said he thought he could get a group of Americans to win at handball. Luka Doncic disagreed.
https://olympics.nbcsports.com/2020/02/05/luka-doncic-warns-jay-cutler-team-handball