Cancelo was a player we were trying to register in the same season and La Liga considered it a way to overcome FFP if a player we buy.
Never mind it wasn't confirmed. It has nothing to do with what Messi983 proposed.
He is literally proposing the Roque deal we did in the same summer and it was allowed, because La liga itself didn't have to be noticed about it until we bring him and the sale officially kicked in.
It is a standard practice, I am not sure what is the fuss about.
Again brother, No!
As of July 2023 when Barcelona signed Victor Roque for 30m+10m, his contract was considered as part of Barca's liability and used in calculating the FFP threshold for Barca. The only additional thing that came in January 2024 when he officially joined, was his salary. Even at that, the small salary cap that was used to register him was based on discounting 80% of Gavi's salary.
According to many sources, even 80% of Gavi's salary was not enough for La liga to accept the registration of Victor Roque, some Directors had to put in personal bank guarantees in order to register his salaries in January 2024.
Please take a read of the La-Liga FFP(officially called Economic Cost Control Rules in Spain), get the understanding first. I am sure you would have a different view after that
Messi for instance, does not have any contract with Barca now but he is being owed salaries from previous contracts. La-Liga considers that when computing FFP for Barca because it is a commitment, a liability, future cash-outflow expected based on past contracts. He does not need to be playing for Barca or registered by the club for La-Liga to include his outstanding salaries as part of Barca's liabilities and thus limiting the spending cap.
I guess what is missing in your post is the knowledge of how La-Liga FFP works otherwise its a pretty straightforward thing. Google works too.