I did another test yesterday. No costum files. And values seem to be almos all fine (weird one is only Gyokeres from sporting with 30). I think the problem is that when using real results + date in the future, FM only gets results, but all other team and player stats are 0.
So if you then simulate half a season or more, top players only score half the goals and and play half the games, so that might affect their values. The weird thing is that each test i did, different leageu got affected.