I guess you mean, clear the database of all players clubs. I don't know if there's one online, but to clear all players of their contracts, it will take a while but
Search in the players search bar on editor and let all the results come up, if you don't have the 500 records thing, this will take an age (but you'll only have to once).
Go Ctrl+Shift, to select all the data, hold down ctrl, click one once to unselect, then double click. It'll come up with X amount of players and a blank file. Go down to club or contract (can't remember which) and change the contract to none. Thus deleting all contracts to clubs, making everyone a free agent, then just saved the database and load a new game, then select.