Marvel's Avengers: Endgame Earth's Mightiest Heroes unwittingly created an alternate timeline in which he survived - and had the Tesseract.
By all s, Loki will somehow learn to use the Tesseract to travel in time - the latest expansion of Yesterday) has been confirmed to Tom Hiddleston as co-star. But who could she be playing? There's been intense speculation that Loki could introduce the Enchantress, a classic Thor villain, but Di Martino doesn't really feel like a good fit for that particular character.
A more likely possibility is that Di Martino could be playing Verity Willis, one of the most important human characters to ever cross paths with Loki in the comics. Verity was born into a family of Asgardian cultists who protected the Casket of Ancient Winters, and who had been entrusted with the Andvaranaut, a mystic ring that allowed them to see through any deception. Her father had left the ring unattended for a moment while she was a baby, and Verity had swallowed it; the ring dissolved inside her, granting her a low-level superpower to see through any lie. That ability left Loki somewhat astounded when he first met her, and she effortless saw through his deceptions and illusions. Verity became something of a sidekick to Loki, allying with him and helping him believe in the possibility that he could be redeemed through genuine friendships.
It's not hard to see how this story could be adapted for the MCU. The Avengers. Thus it's entirely possible Loki could have a redemption arc once again, albeit a very different one.
This could even potentially explain the time travel element of the Loki TV series, as the curious Trickster God explores history attempting to figure out how Verity came by this strange ability. If so, then Disney+'s Loki show would also reveal the history of Asgardian interference on Earth - a fascinating new side to the MCU.