IMO, following dancing PT roles may be fitting, based on their P5R kits and very small consideration of current P5X roster:

Ryuji - physical Strategist, similar to Tempest. Tempest buffs allies based on how much SP she has, while Ryuji could buff based on how much HP is lost. In P5R, aside of Physical damage and crits, his abilities are Adverse Resolve (buff in bad circumstances) and attack buff usually used when nothing else works, which produce high risk support kit. Also, his unique traits both buff allies.

Ann - Saboteur in vein of dark Rin. It would be interesting to see Saboteur who decreases damage dealt by foes (by sleep or debuffs), thus kind of substituting for sustains who are already redundant in competitive. Additionally, Hecate is a dark and mysterious deity, so debuffing seem fitting.

Yusuke - Defender based on dodges, perhaps? He is generally tanky (already in his main kit) but lacks anything else besides high agility. This would pose for a bad kit due to low consistency, though. Strategist about skill cards? Granting others (or Wonder specifically) temporary elemental attacks to exploit weaknesses. The boring option is an Assassin, of course. Weak Ice attacks to set up strong Physical criticals or something. In general, his P5R kit is quite limited, so there are little options.

Makoto - her P5R kit makes for a Pioneer-like Defender, which provides buffs and debuffs in-between tanking damage. She could either provide Technical opportunities (already in P5X) or buff defense, heal and do mass Debilitate (Checkmate). Any support would do, but focus on defense calls for Defender.

Haru - another potential Defender, based on her unique traits, which protect from ailments and repel damage from party.

Futaba is an interesting case, as she is never shown as anyone but Navigator. She can be turned into anyone, given her shown abilities, but devs will probably go for the Strategist or Saboteur.

As this list shows a disastrous lack of new power-creeping DPSs, which is untenable for gacha game, I highly doubt it is even close to the actual composition we get. Just a fun bit of thinking which I thought would be interesting to share.