I've had similar experiences with Brexit. I've managed to get Boston United from lower leagues up to League 2 currently. It has taken me about six seasons so far, but now Brexit has happened. I think it's a reasoanbly soft Brexit, as I am allowed 17 European players. That said, they still ALL need permits, which is proving a nightmare. I managed to find a 16 year old from Portugal who has a lot of potential. I got him on a free, and received him just before Brexit occured. As soon as it occured he now needs a permit. As a lower league club with no WP afiiliates I don't even know if its possible for this lad to receive a permit. It will take 1800 days for him to attain British nationality, which will mean he will be about 40 before I can play him.
Just to add, I think we need some clarification. I am presuming that you can still get these foreign wonderkids; you just have to get a permit for them regardless of their nationality. So even if one is from the deepest, darkest Peru, for example, providing you can send him to a feeder he will attain a permit eventually.
Also, if you want permits for South American players, send them to Spain. It's just 2 years to attain Spanish nationality, then I 'presume' they can be awarded a permit.