Button hover colour change

Like @MDS mentioned, it is worth to take the time reading about the use of classes.
This is a major and very powerful tool in blocs if you want to optimize your design.
These screenshots for your idea might help:

Create a class, e.g my-hover-button
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Than choose “hover” to work on your design

I would also suggest to join @Eldar ´s videos, super helpful for beginners