"We try out the partnership" feels unnatural in English to me, unless the person speaking is not part of the partnership. If the idea is that the person speaking is trying to partner with someone and they are doing it on a trial basis, I think one would say "we try out a partnership". I'm trying to imagine some natural dialogue in which "we try out the partnership" makes sense, but it's difficult. Am I getting the meaning completely wrong?
It does seem awkward, but I can imagine a situation: For example, we have been considering whether to have work done by a carpenter who has worked for us before, with indifferent results. Across town, there is a small carpentry firm--a partnership. We don't know how good these carpenters are, but we decide to give them a try. Thus, we try out the partnership.
You could say the same thing about other present tense constructions, English versus German. Generally in English we say "we are [doing whatever]" whereas in German you'd say "We [do whatever]." In English, if you say "We do" we don't mean that's our current action in progress; we mean that we commonly do that, even if we aren't doing it right now.