yeah regens normally get youth contracts, as a general rule of thumb virtually all real players start the game at 16 or older so to find regens i look for players age at most 16 plus the number of years my save has ben going, so i wouldn't even bother looking in the first year until i got to the youth candidates time of year.
like the others said, but if your in europe and u sign a Argentinian regen, then wont join u until they are 18. thats the rules, again. u-18 (or u-17) players cant move abroad until they are 18 or 17