I enjoy and feel down at the same time. ¿

Улий, I dare say that your translation does not cover "одновременно" part.

Thank you!

Do you approve my 2 versions?

The first one is good, but the second one should read “get satisfaction... FROM IT at the same time”

But the original question did not have anything pointing at IT. It is in generally saying получаю удовольствие и впадаю в грусть ...

It’s hard to explain. There’s a concept in English called VALENCE which refers to the number of grammatical elements with which a particular word, especially a verb, combines in a sentence. In this case, the full expression is “to derive/get satisfaction from/out of something.” To the English ear, if you don’t mention the FROM or OUT OF, the sentence sounds MARKED - even if it’s grammatically possible. One way to fix your sentence, is to replace GET with a verb that doesn’t have the same valence as GET in this context, like FEEL: “I feel satisfaction and sadness at the same time,” for example.

Having said that, your sentence is perfectly correct without FROM/OUT OF - it would just sound better with it.