I never work with so many subclip, so I don’t know if there is an issue with copying subclip between 2 projects.
I can try to write a script to export a subclip list and another one to import this list in a project.
If you are interested, please contact me via the SCS forum (Rosebud): https://www.sonycreativesoftware.com/forums/ShowProfile.asp?UserID=4710