In this transfer window, Barcelona spent less money than we could even expect to see from them, Among all the teams in the Chmapnis League Barcelona spent even less money on Young Boys, while maybe some people don't even know Young Boys but these teams spent more money than Barcelona.
They are trying really hard to have better financial situations however these teams still get good results.
Also, PSG is at the top of the list.

Maybe if Chelsea played in the Champions League they would be in first place beating PSG and several teams from the English top league because Chelsea spent at least more than 400 million euros, a fantastic figure.
FC Barcelona only spent a small amount because that is what they had to do otherwise sanctions would be possible.
Successfully winning in the first match against Antwerp cannot yet describe Barcelona is a successful team in the Champions League this season because the journey is still very far away, but seeing Joao Felix score two goals, it seems like this player has regained his passion for playing and Barcelona is not spending a lot of money on this player very lucky, especially if he is consistent at Barcelona.