He's got a solid chance to break the record for # of assists in a La Liga season. Xavi currently holds the record with 20 back in 08/09 season.
Leo's sitting at 17 right now with 6 games left to play, his personal record is 18 which he's hit twice in 10/11 and 14/15. If he goes ham and manages to hit 21 or 22 in La Liga then he might have been able to challenge for most assists in all competitions for a season in Europe if not for COVID-19. I don't exactly remember what the figure was for that but it's anywhere between 30-35 held by either Xavi or Messi himself. The problem is that the CL is only 1 leg ties from now on so there are far fewer chances to do it, and we got knocked out of CDR fairly early.
There's definitely no way he hits the tally for the European record but he could get to the upper 20's for a season which would be remarkable considering the team and the overall circumstances this year.
Regardless, I think his best season ever in terms of passing was still 18/19 season even though he "only" got 13 assists, he was just pinging jaw-dropping balls over the top like it was nothing. Many of his most aesthetic passes are from that season.
Leo is in really bad form with his shooting though, he's probably pretty frustrated with himself honestly. Looked like he was forcing it a few times today. Other than that, his dribbling and playmaking have been on point for sure.