Thank you for the update.
When looking at the files you sent us, we couldn't find any players in either file who's nationality has been set to the new nation, so no players from the leagues can be selected for the new nation's squad.
Hello,
1. Thank you for raising this. We will put under review.
2. This is by design.
3. Can you please send us your exported team along with your save file where you exported the team from.