Change Picture of variant based on the first variant

[MOYU]

Hi, I want to create a bundel system where people can select 2 items to create a bundel. To achieve this i:
Created 2 variants, Book 1 and Book 2.
For Book 1 you will have 4 Options, and for Book 2 also 4 Options.
I want to be able to see the change of the second variant image based on the First variant. You can see the change in the big main image, but not in the small variant images.

I attached a few pictures to better help understand my problem.

I hope i'm clear enough, if not please email me on Tim@moyu.rocks.

Thanks 🙂