I tried replacing Mitsuru's model with Kotone's (using a DeathChaos' mod that replaces Fuuka with Kotone's custom model) and was able to retarget these animations thanks to FoxShrine's tutorial, but in the end, all the duets and dances work fine except for the DLC songs (Today, Break Out Of... and Battle for Everyone's Souls)
I've attached two videos: the first is the full duet part, and the second shows the imported and retargeted animations in Blender and how it should look (at least, since I want to fix the hand placement later).
Another issue that concerns me is the lack of GAP files for most of the costumes (and hair) for these songs. I explained what this looks like as best I could in the 3rd attachment.
I tried importing and exporting animations through Blender, slightly changing the hand position (to test the theory that perhaps Mitsuru's hand was somehow attached to Shinjiro's), but still no luck. I also saw a video from DeathChaos where Kotone was in place of Akihiko and Elizabeth (DLC songs too), but I haven't tried replacing their models and animations myself yet. https://youtu.be/EKIbefsIqf8?si=La-P3yjinvDhUPvF
Has anyone encountered this? Is this somehow related to "addcont" folder with all the DLCs? I would appreciate any help or suggestions.
Just testing out some model swaps with hair models, as well as having her replace different dancers to make her dance with a certain beanie wearing Senpai and a certain elevator attendant...