Below would be the roster lists, so if you're happy with who is in 2K24 I would say go ahead and just purchase that given it is likely a lot cheaper.
Click here the Official WWE 2K24 Roster List of all your favourite WWE Superstars - check in regularly to find out which Superstars are on top!
wwe.2k.com
“The Original Tribal Chief” Roman Reigns and the iconic Undertaker are this year's featured Cover Superstars. View the official WWE 2K25 roster here.
wwe.2k.com
Would recommend just getting the base games and then you can buy add-ons later if needed. There is a "Supercharger" which is like $10 or so which helps unlock all the characters from the roster list, otherwise some of them you'd have to play and earn points in order to unlock which can be time consuming.
They also have "season passes" which include 5 character packs released throughout the year, or you can buy the separate character packs if you want any certain wrestlers.