I don't think Barcelona have the strength of moving around in transfer window because of their financial situation now, even before the starting of the season it should be better Barcelona to agree to just stay behind real Madrid because they can stand it, second place is for them the earlier the believe it better for them, Real Madrid are currently the most strongest teams all over the world not Laliga alone, and they are fit to play and win any of the competition without any fear. Among all the leagues, I think only home league required a consistent performance to be able to maintain it, and already they are built in that.
Barcelona deteriorating finances are indeed a barrier for Barcelona to recruit and fix their squad, even reportedly currently Barcelona debt has been quite large so they have to sell their broadcasting rights and also some merchandising licenses to cover their finances, currently Barcelona is in a very difficult condition to compete with the strong teams in La Liga today, Barcelona, of course, still has ambitions to continue to be able to compete in domestic championships and European competitions, but indeed their finances are a barrier to being able to get achievements as was the few seasons ago, currently in addition to selling some important assets for them, Barcelona is now trying to compete by relying on players who come from the academy and also those they get with the status of free transfers.
Looking at the strength comparison between Madrid and Barcelona today, of course we can see a significant difference between the two, so what you say is quite true, it will be difficult for Barcelona to be able to compete with Madrid in the current financial condition and even so far Xavi admitted that if Barcelona financial condition will not be able make their to compete with Madrid, Currently, Madrid has improved their squad well enough that Lewandowski also admitted that Madrid with Mbappe will be scary next season.