Vision, who is strangely alive in the latest series of WandaVision, may not be worthy of Thor's hammer. There have been speculations that Vision might really not be worthy of the Mjolnir at all and while he can lift it, he cannot summon its powers.
For one to be able to be worthy of the Hammer of Thor, Odin whispers to it that, "Whosoever holds this hammer, if he be worthy, shall possess the power of Thor." Dissecting this inscription, one must, first, be able to hold the hammer, and second, be worthy to possess the power of Thor. This was perfectly executed by Captain America in the Avengers: Endgame, he was able to summon the powers of Thor and strike a lightning bolt to Thanos because he fits both of the requirements.
Silly as it may sound but the argument between Tony Stark and Steve Rogers at the end of Avengers: Age of Ultron about the elevator, an inanimate and surely unworthy thing, can bring the hammer up and down, kind of makes sense when it comes to Vision. Vision, being a humanoid, as clearly seen in the second episode of WandaVision where there are elaborate explanations as to his bodily mechanisms, may be likened to the elevator in question. When Vision held the hammer, there were no lightning bolts coming with it compared to when Thor or Captain America summons it. This could only beg the question: Is Vision worthy?
Maybe the Mjolnir can detect a person and a thing? Maybe the Mjolnir needs a pulse to function? Or maybe, the Mjolnir is just choosy as to who is worthy of carrying it. Whether or not Vision is worthy is something that MCU wouldn't be able to address anytime soon as Vision is still dead in real life and there is still no answer as to how he is alive and with Wanda in WandaVision.
WandaVision is canon in the MCU and its events are taking place after that of Avengers: Endgame. In a classic sitcom style with black and white, the series pays homage to ‘50s and ‘60s shows exploring a new way of telling the story of the MCU. It will be released weekly on Disney+.
The next episode of WandaVision will be on Friday, January 22, 2021.