The introduction of Clea will have a significant impact on the MCU.
In the first after-credits scene of the movie Doctor Strange in the Multiverse of Madness, Clea - a crucial character from Doctor Strange comics, made her big-screen debut.
Since then, many fans have wondered about Clea's role in Doctor Strange's story and the MCU's future.
1. Acting as a 'bridge' to delve deeper into the Dark Dimension

In the first Doctor Strange film, Dormammu was depicted as the ruler of the Dark Dimension - a realm dominated by the Mindless Ones, a race resembling humans proficient in magic, marking its most peaceful era.
When Dormammu appeared, he led the ruler of the Dark Dimension, Olnar, into a space called the Mindless Ones. As a result, Olnar went mad and caused the death of millions of residents in the Dark Dimension. Chaos ensued, providing Dormammu the opportunity to wipe out numerous Mhuruuk races before rising as a god to end the war and control the world.
Now, Clea's appearance will shed more light on the Dark Dimension. Clea originates from the Faltine race within this realm. She is the daughter of Prince Orini and Umar – Dormammu's sister. Due to Dormammu's frequent attacks on Earth, Clea crosses paths with Doctor Strange.
2. Being Doctor Strange's greatest love

Clea's arrival comes at a very opportune moment in Doctor Strange's MCU version. In the second film, Strange reveals his human side, particularly his heartache when his long-time lover, Christine, gets married.
But Clea's presence once again stirs Dr. Strange's heart. Both met when Doctor Strange ventured into the Dark Dimension to confront Dormammu. Initially, she sought to hinder him, but eventually sided with Doctor Strange, impressed by his bravery.
For this betrayal, Dormammu captured Clea and nearly killed her, but Doctor Strange rescued her. Afterwards, the heroine moved to Earth, becoming Doctor Strange's apprentice and lover. Clearly, Clea's presence also serves to provide a romantic yet intricate dimension to the character of Doctor Strange.
In the realm of possibilities, Clea could emerge as the successor to Doctor Strange in the future.

Their relationship in the comics has weathered various storms, but Clea stands as Sorcerer Supreme in one timeline, succeeding her husband under the moniker Clea Strange.
This narrative thread could seamlessly weave its way into the MCU, where Clea might ascend as the new Sorcerer Supreme, filling the void left by Doctor Strange.
Such a storyline holds promise for the future of MCU, with Clea potentially stepping into the formidable shoes of Doctor Strange.