Greetings,
Many Swiss banks do not finance properties outside of Switzerland. Some will provide home loans if the property in question is located in a specific country.
Crédit Agricole Suisse, for example, accepts mortgages for holiday homes and investment properties in France - albeit with special amortization and down-payment requirements.
In the case of a property in Germany, you may be able to get a mortgage from Swiss banks located close to the German border. Various factors, including the property in question and your financial situation will play a role, and each bank will have its own set of guidelines.
Consider requesting quotes from various banks in regions which border Germany to find out which banks will accept your mortgage and under which conditions.
An overview of Swiss mortgages can be found in the interactive mortgage comparison on moneyland.ch.
Best regards from Moneyguru