Something like a "Mean" Mark Callous Persona Card or outfit would also make sense given that they've been dabbling in WCW-era versions of the roster with Terra Ryzing in WWE 2K24 as a Persona Card.

Dangerously in WCW and ECW. He managed some of the future greatest names in WWE, including “Stunning” Steve Austin, “Mean” Mark Callous (The Undertaker), Taz, and Sabu, among others ...

Covers The Undertaker's career from his arrival in NWA/WCW as "Mean" Mark Callous as the replacement for Sid Vicious in the Skyscrapers through his first "Decade of Destruction" in WWE ...