According to reputable sources speaking to Deadline, actress Sophia Di Martino is going to co-star in the Disney+ Loki series alongside Tom Hiddleston. The big rumor about her part in the series is that she won't just be sharing the spotlight with Hiddleston, but that she'll be sharing the same character, too, as a female version of the titular Trickster god.
Of the various Disney+ series announced, Loki has so far been the one without the clearest hook selling it. We know that Falcon and the Winter Soldier will determine the future of the Captain America mantle; WandaVision is going to take a completely original sitcom-horror hybrid approach, while future shows like Hawkeye and Miss Marvel will introduce all-new heroes possibly building up to a Young Avengers team, but Loki has been a bit harder to get excited about.
Remember that the Loki in this series is the Loki that left with the Tesseract after the Battle of New York in Avengers: Endgame, with none of the character development that enriched the character in the later Thor movies. Even rumors of a time-travel plot sound a bit "been there, done that" after Endgame and, with the promise of relevance to future MCU films, what could this show bring to the table that would feel fresh?
Exploring parts of Loki's character that the movies didn't would be the surest route towards making this premise interesting, and one significant aspect of Loki the movies have not addressed at all is their genderfluidity. As a shapeshifter, Loki in the comics frequently shifts between male and female forms. Importantly, not only is Loki's physical form fluid but their gender identity shifts around as well. In different states, Loki is alternately referred to by either "he/him" pronouns or "she/her" pronouns; for the purposes of this article, Loki will be referred to with "they/them" pronouns when their specific gendered state isn't specified.
The long speculated-over nature of Loki's genderfluid identity, as well as their bisexuality, was confirmed as canon in 2014 and delved into in greater depth during Jason Aaron and Al Ewing's work on the books, Loki: Agent of Asgard and Original Sin: Thor and Loki - The Tenth Realm. These books made it clear that Loki's physical sex transformations were not merely for practical purposes (as could be argued of the case of Loki possessing Sif in Avengers: Disassembled) but also reflective of their psychological sense of self. Odin even refers to Loki as being both a son and a daughter! Mackenzi Lee's YA novels about Loki have also portrayed them as openly genderfluid and pansexual.
It's also noteworthy that Loki went through a more personal queer identity exploration when he became part of the Young Avengers after their death and rebirth in the "Seige" arc of the comics. Given that the other Disney+ series almost all seem to be pointing towards a Young Avengers team, we can easily imagine that storyline being set up.
The Marvel TV shows have been far less shy about presenting LGBTQ characters than the movies have been thus far. The same is true of Disney properties as a whole; shows on the Disney Channel have had far more queer representation than Disney's movies, and Disney+ has already picked up LGBTQ-inclusive series such as a new spinoff of Love, Simon. While there might be pushback against exploring Loki's gender identity and sexual orientation, it still seems like something well within the realm of possibilities for the Loki Disney+ series.
A genderfluid Loki offers up fresh possibilities for the MCU, while also staying true to the comics (to say nothing of the original Norse mythology). If Sophia Di Martino can command the screen as well as Tom Hiddleston, then seeing Loki's female form on screen is sure to be a delight. This would be a good decision for the cause of on-screen representation, but also for the simple universally agreeable cause of new and interesting storytelling.
Loki is scheduled to premiere spring 2021 on Disney+.