Scarlet Witch's Phase 5 Return Was Prevented by the Last 4 MCU Movies. 

Because of the last four Marvel Studios movies, 

Elizabeth Olsen's Scarlet Witch won't be making a comeback in Phase 5 of the Marvel Cinematic Universe. 

Wanda Maximoff undergoes quite the journey in Avengers: Age of Ultron, 

starting off as a villain on Ultron's side, switching to the Avengers, and losing her brother, Pietro. 

Following that, Wanda's MCU journey would continue to be full of horrific experiences,  

which would eventually come to a head when Vision was slain by Thanos in Avengers:  

Infinity War and the Scarlet Witch in Disney+'s WandaVision opted to construct her own world out of sadness.

After letting go of her identical twin sons Billy and Tommy at the conclusion of WandaVision to restore reality,