You must understand that what a physicist (real physicist) thinks of when they hear wormhole is a very particular mathematical subtlety in a solution to Einstein's equations. True, some people have put in some legitimate work to study the properties of similar such bridges connecting two regions of spacetime, but all of these constructions are artificial in the highest degree. That is, although they exist as valid solutions to the Einstein equations (although it is not clear if they are possible/stable when quantum corrections are introduced), it is impossible to find them in nature.
Science-fiction authors then took the idea of wormholes and twisted it around so much that it does not even resemble the original idea.
Furthermore, even if there did exist a traversable wormhole between two galaxies in our own spacetime, that would in no way account for the overall rotations of the galaxies being similar. Which is assuming that there would be galaxies with identical rotations (there are not). The phenomenon are simply completely independent.
It is true that we do not know everything, especially considering the quantum-gravity corrections that will undoubtedly muddle the true nature of black holes, singularities, and worm holes. However, the purpose of this forum is to educate people as to the current state of knowledge, not to engage in wild speculation.
If you're actually interested in wormholes as mathematical objects, I suggest you read:
https://www.amazon.com/dp/1563966530/?tag=pfamazon01-20
After you have had some training in general relativity and quantum field theory.
