Reed as a sociopath is 'The Maker' ... I think we'll see a classic Reed, but also a recent take on Richards as The Maker.
There are a TON of rumors floating around the future of the MCU dropping Jonathan Majors and Kang as the next big bad. After watching Loki S2, I do think they pivoted and will be dropping Kang. We'll know for sure when there's no longer a Kang Dynasty film. The recent MCU work has been based on Jonathan Hickman's multi-year comic runs ... multiverse / incursions / Illuminati / Secret Wars ... all Hickman's stuff. Comic fans tend to either love or hate Hickman (I love his stuff), but he primarily focuses on 'world building'.
My wild swing is that they'll use the F4 and the 'Council of Reeds' in place of the Kang Dynasty. The new big bad in place of Kang will be The Maker, evil Reed Richards from the same universe as Miles Morales (earth 1610)
https://en.wikipedia.org/wiki/Maker_(Reed_Richards)
Personally I'd love to see Disney to keep Krasinski in the Reed role since it's a multiverse, But Mr Pascal is a great choice as well.
The MCU is a pretty big mess right now, but if Secret Wars does end up being a reboot ... and Hickman is currently rebooting the 'Ultimate' universe in the comics ... I'm leaning towards Evil Reed being swapped out for Kang meaning Disney will need big name in the Reed role.