Im honestly not sure what the plan is here with bringing RDJ back to play a completely different character, i have to assume he is playing the doom from whatever earth the MCU fantastic Four are from and he just happens to look like earth 616 Stark, especially since the Russos said he was Victor Von Doom and not Tony Stark, so that takes the Stark Variant idea off the table, idk, i am as puzzled by this casting as most people are, especially since RDJ has been the face of the MCU from 2008-2018, and many fans i have seen since endgame miss as Tony, if this is some round about way to bring Stark back these seems an odd and overly complicated way to do it, which i dont believe there will ever be an Iron Man in the MCU again, so idk, hard to get excited when there are talented actors out there that could easily be a good Doom, bringing back your biggest star to play a new role seems desperate? IDK