A lot of the MCU takes inspiration from the Ultimate Marvel line of comics, as is evident in characters like The Hulk, Iron Man, and Nick Fury. Given that the X-Men and the Fantastic Four will now be heading to the Marvel Cinematic Universe as well, it stands to reason that they might emulate their Ultimate Marvel versions as well.
With the Fantastic Four making their debut in the Marvel Cinematic Universe, it stands to reason that they might, too, take some inspiration from their Ultimate Universe counterpart. While Reed Richards of the Ultimate Marvel continuity would end up becoming The Maker, Ben Grimm would get a much radder update which might be something Ebon Moss-Bachrach would be keen on exploring in the MCU.
Ben Grimm might be able to shift between his rock and human forms in the MCU
Ben Grimm is famously stuck in his rock form, which leads to a lot of angst for the character, given that more often than not, people see him as a monster. However, the Benjamin Grimm of the Ultimate Marvel timeline received an upgrade, that allowed Ben Grimm to switch between his human and rock forms, while also giving him a slew of other powers.
In the Ultimate Marvel continuity, Benjamin Grimm’s rock form is actually just a stage in the character’s metamorphosis, where The Thing transforms into a being of energy, similar to Wonder Man. This version of the character looks markedly more human and can shift between the monstrous rock form, and a more human-looking form.
While Ben Grimm of the MCU is probably going to be a mixture of CGI and practical effects, Ebon Moss-Bachrach could explore this version of the character, allowing his face to be associated with the character, rather than being buried under practical effects and CGI.
There has been a lot of speculation about The Maker being the next big antagonist in the MCU
Given that 2015’s Fantastic Four took inspiration from Ultimate Marvel as well, Miles Teller’s Reed Richards might be primed to become the Maker, an evil version of Reed Richards.
Given that Doom, Kang, Thanos, Loki, and Ultron have all been exhausted (with Galactus also possibly being just a one-time villain), The Maker would serve as the perfect antagonist for the Fantastic Four and the X-Men in the MCU, right out of the Multiverse Saga.
This could be essayed by Miles Teller, who could either make an appearance in the MCU as a part of the Council of Reeds or as a multiversal villain that gets assimilated into the Marvel Cinematic Universe along with the rest of the Marvel Legacy characters.
The Fantastic Four: First Steps is set to release on 26th July, 2025