Yes there is! I am participating in a virtual league in OOTP21 called “Our League “… Not a very imaginative name but you get what you get. The rules are that you can only be a free to play team, which means the only PP you can use are the PP you earn from your team’s achievements. You are not allowed to purchase PP for your team. In addition, this league does not allow the use of Live cards, just historical. It’s a ton of fun, IMHO, and kept me engaged a lot longer than I would have played if I’d just been in a random league (since I am unwilling to dump large amounts of cash into a team).
How it works is that you friend other players who have OL teams, and if everyone friends everyone else and selects the “use friends list” placement for leagues you end up placed with other OL teams at your level.
Even though you are placed in a league with non-OL teams, we track your record versus other OL teams only so our standings are based on those records.
Of course, you don’t end up in a league with just OL teams but over time more people will join this league and you’ll get close. In fact, last year, there was a perfect league that had just OL and free to play teams in it for a long while.
There is a thread in the OOTP forums about the league: Looking For "Friends" to join "Our League" Season 3 - OOTP Developments Forums
If you have any questions feel free to ask me!
There’s no requirements to prevent people from joining except for the fact that you cannot have spent money purchasing PP for your team… So if anyone else is interested, feel free to check out that thread.