Xavi with Barcelona had a good performance this season and even if you are talking about the games they lose this season and the game they lose in the Europa League still Xavi is not experienced enough and in the next season when Barcelona plays in the Champions League Xavi can have much more chance to achieve something there.
The Champions League will be very different for Xavi, he has experience as a player but as a manager is still very minimal so Barcelona might be doubted to be able to do more in this tournament next season, even though they have a lot of experience as champions league champions but the current line-up is much different which will also give different results, especially regarding the issues that still exist about Barcelona might distract them from their focus, and the most important thing at this time is to find replacements for the players who have been confirmed to leave Barcelona, especially since these players have a big role in Barca, their departure could greatly affect the appearance of the team, and with financial problems that are still hitting what they can do in the current player transfer season, it is still very much expected that there will be surprising news about their success in bringing in great players who can help them win more trophies next season.