Basically every single spellcasting subclass has reasons why they should each possibly have a different one of the three mental stats as their primary casting stat. Psionic Sorcerer could use INT... Enchantment Wizard could use CHA... Celestial Warlock could use WIS... and so on.
If it matters that much, and having two mental stats (CHA and INT) as high stats is an issue (because whatever feelings towards character optimization one might have)... then one needs to make arrangements with their DM to see if they are okay with switching the Psionic Sorcerer from CHA to INT.
If it matters that much, and having two mental stats (CHA and INT) as high stats is an issue (because whatever feelings towards character optimization one might have)... then one needs to make arrangements with their DM to see if they are okay with switching the Psionic Sorcerer from CHA to INT.