Pet ownership transfer information between Switzerland and Germany

Hi, I am moving back to Germany (Munich) next year and I was planning to adopt a pet. Recently, the cat of a good friend of mine, who lives in Switzerland (in Lausanne), gave birth to some kittens. I thought it might be nice to adopt two of these kittens, however, I have not been able to find information about how to legally proceed with the adoption. I have read the information about cat registration in Switzerland or the import of cats in Germany. For the last one, it seems it is necessary that the pet has an EU passport, required vaccinations and microchip. However, to get the passport in Switzerland it has to be registered in their database, for which only people who live in Switzerland can do that.
I was then thinking that perhaps the easiest thing to do is to get my friend to register the cats, get them vaccinated and microchipped and then travel with them to Germany and perform a transfer of ownership. I was wondering where can find more information about this process or which department should I contact to clarify how to best perform the adoption legally in Germany.