I doubt that honestly.
Raphinha is in his best form these days. Why would Hansi Flick decide to cut him from the starting lineup to "rest"?It doesn't make sense while he is one of top goal contributors. Rashford will need to earn his place there. He will need to work hard to stay fit and impress the manager. I can't say he has been in his best physical shape recently.
https://www.mundodeportivo.com/futbol/fc-barcelona/20250721/1002503443/marcha-revision-medica-rashford.html
This deal doesn't seem to be favorable for both sides, because Rashford hasn't played well at a high level for about 3 years and Rashford should say 'thank you' for Emery that gives him a chance to play at Aston Villa. For the other side Barcelona have a huge number of their youngsters like Pedri, Gavi, Ferran Torres and other young players who are ready to play and can bring more value to Barcelona than Rashford, who is likely to lose the competition and will sit on the bench until the end of the loan.