Well, you both have to be at least 35 or have been married for at least 5 years.
Adoption by a couple
If you are a couple wishing to adopt a child, you should:
•have been married for at least five years or both be at least 35 years old
•both be at least 16 years older than the child.
More info on the whole thing here:
https://www.ch.ch/en/how-adopt/
Whether there would be any language requirements may depend on which canton you'll be living in. Best to contact the relevant authorities in Zurich and Zug and see what they say.