I think this movie will be having some very important role
Honestly, I’m totally convinced Emilie wasn't the angel everyone makes her out to be. Think about it: Adrien was kept isolated and banned from going to a normal school way before she ever 'disappeared.' That level of control started with her, not just Gabriel.
That’s why I think the Solitude movie is going to completely blow the lore wide open. The plot of that film is almost definitely huge foreshadowing for how Miraculous is going to end, or at least how the next generation’s story will unfold. It’s too specific to just be a random easter egg.
Plus, we need to talk about the 'Group of 4' from the past Gabriel, Emilie, Audrey Bourgeois, and André. Their connection is way darker and deeper than we think. We’re already starting to see Audrey’s true involvement and how shady that whole circle was. Solitude might literally be a hidden documentary or a mirror of the corrupt things that original group did to get their power and status. It feels like Adrien and Marinette are just scratching the surface of a generational mess.