Final Fantasy Resonance is looking like it's going to be a huge celebration of the series, featuring characters from across the entire history of the franchise. Almost every game is represented in some way via the game's fancy Visions system, which lets you have a summonable character at your back at all times.
However, for those in the know, you'll know that this is actually a semi-remake of Final Fantasy Brave Exvius, which is a mobile Final Fantasy game that included a lot more crossovers. And, due to the two being very similar, someone has already made a mod that lets you turn any of the 1,800+ units in Brave Exvius into a Vision in Final Fantasy Resonance.
This mod was seemingly created by a team called FFR Vision Studio, and it will allow you to drag pretty much any of the units in Brave Exvius and add them to Final Fantasy Resonance as a Vision. Unfortunately, you do have to give said character their own movesets and abilities, so it's not quite drag and drop, but it does allow you to have some pretty wacky crossovers in the FFR demo.
For example, if you want to have Sora from Kingdom Hearts 3 backing you up in a battle, you absolutely can. What with Brave Exvius being a mobile title, it wasn't all that concerned with how absurd a crossover was, which means you can also have characters like 2B, Lara Croft, Adam Jensen from Deus Ex, and even Rico Rodriguez from Just Cause.
There are also plenty of partnership crossovers to choose from, such as the aforementioned Sora from Kingdom Hearts, as well as Edward Elric from Full Metal Alchemist. There are plenty of Dragon Quest characters too, and you can even go into battle with Ariana Grande or Katy Perry if you like, what with the two having been featured in Brave Exvius in the past.
While it's just the demo right now, I don't see why this mod won't make it over to the main game when it launches this October.
سەرچاوەی فەرمی بە زمانی ئینگلیزی: https://www.thegamer.com/final-fantasy-resonance-mod-sora-2b-ariana-grande-visions/