[MENTION=227392]ggdaris[/MENTION] [MENTION=238087]Speckkopf[/MENTION] if you want to do this in PES 2019 here's some math to help you:
PES 2019 teams avaiable for editing:
Premier League - 18
Championship - 24
La Liga - 19
PEU League - 20
PLA League - 20
Other Latin America - 21
PAS League - 20
Other Asia - 16
Total: 158 editable teams
FIFA teams (total) = 211
FIFA teams already in game = 81 (34+10+17+6+14)
FIFA teams that need to be made = 211-81 = 130
Remaining slots = 28
Teams that are part of a Continental confederation but not FIFA (like Northern Mariana Islands, Zanzibar, etc.) = 11 (there are 12 but I think you can exclude Niue which is a member of OFC but I don't think they ever played recently)
Remaining slots = 17
So, if you keep a few teams from Premier League (Chelsea, Man. Utd, Man. City, Tottenham) and a few teams from La Liga (Real Madrid, At. Madrid, Valencia, Sevilla), you still have 9 slots for Non-FIFA teams (or more, if you give up more teams. Perhaps giving up Tottenham and Valencia/Sevilla and you'd get 11-12 slots. Or even getting rid of all of them. You won't be playing club vs national team anyway). You have to choose them between Greenland, Monaco, Vatican City, Jersey, Guernesey, Alderney, Isle of Man, Anglesey, Northern Cyprus, Aland Islands, Tibet, Micronesia, Palau, St. Pierre et Miquelon, Falkland Islands, Mayotte, etc. since you won't be able to have them all.
Also, if you want, you have 2 more slots in the classic teams.
To do this project in PES 2019, you can use almost every editable team slot in the game so you can have all FIFA members + All CAF, CONCACAF, etc. members and still 9-12 non-affiliated teams. Not as many as we can have on PES 2017 unfortunately, but at least it is possible to do this in PES 2019 if you are willing to give up Premier League and La Liga.
However, I'd still like to see this updated on PES 2017 one last time at least
EDIT: Btw, is there any way we can convert from PES 2017 to PES 2019, like you did with PES 2017 to PES 2018?