MCU’s Phases 3 and 4 introduced two unknown characters that could both end up being revealed as Doctor Doom in the near future. With the announcements of Avengers: Secret Wars, there are many theories going around that Doctor Doom will play a huge part throughout the rest of the Multiverse Saga. While there is no actual confirmation of the character appearing, two specific projects make it very easy to retcon the evil sorcerer into the MCU.
MCU Phases 3 and 4 have introduced the powers of government technology, Pym technology, sorcery, and vibranium, and they all play an important part as Marvel's Phases 5 and 6 get underway. Those four sources of power could potentially be of interest to Doctor Doom, but the MCU can easily connect him to past instances of government and Pym technologies. Pym technology plays a major role in the Multiverse Saga as multiversal travel is a huge part of the projects as well as newly created government technology to combat the out-of-world threats.
Back in Phase 3’s Power Broker, Sharon Carter could be working with Doctor Doom as he may be in need of secret data and unreleased weapons for his evil schemes.
How Black Panther 2 Can Set Up & Introduce Doctor Doom
In the first trailer for Wakanda is the home of the MCU's vibranium, introducing Doctor Doom in an end-credit scene would be the perfect way to begin his journey in the MCU.
There are often little side plots in past Marvel projects that come into play in future projects, and MCU Phases 3 and 4 make that possible for Doctor Doom. There are a number of projects in the Multiverse Saga that can incorporate him into the overarching plot line in many ways. Black Panther: Wakanda Forever is set to release this November and is the end of Phase 4, so hopefully the big reveal for the future in its end-credit scene(s) happens to be an introduction to Doctor Doom himself, and that his connection to either Sonny Burch or Sharon Carter is revealed.