You need to use Twixtor PRO to generate Motion Vectors.
These Motion Vectors can be piped in RSMB Vectors.
You just have to make sure Max Displace is the same.
Assuming it’s parallel view axis you can try:
1) just offseting the MV of one view to the other (a straight translate of the MV image – then some pixels would be missing on one side if you have no padding)
https://revisionfx.com/support/faqs/motion_vector_FAQs/motion_vector_math/
2) If you are in app that supports RE:Map Displace you can try to warp the MV to the other frame using a Motion Vectors Create (in Twixtor) oflow between views
Of course both of these techniques will probably fall apart if there is a lot of parallax between views
There is probably a more convoluted workflow I could come up with but I would need some sample frames
Pierre