score:5
As a US citizen, you don't need a visa if you stay less than 90 days out of 180 and perform "business activities". Which is not "work".
The list of activities allowed for Germany is listed here.
Note that it says:
the following lists are not exhaustive and are subject to individual interpretation. Both lists are meant as a guideline only and do not constitute legal advice. It is the responsibility of travellers to ensure that any activity conducted falls within the scope of permitted activities. If in doubt, you should take legal advice from an immigration lawyer or specialist
(emphasis mine)
The list provides both activities that are allowed and a few which aren't. If you're lucky you fall clearly in the allowed activities (such as training staff, negotiating contracts...). If you're unlucky you fall clearly in the activities not allowed (which will require a work visa). And if you're in between... Good luck!
Upvote:1
I am not a lawyer nor I do have much knowledge about specific Schengen regulation, but...
From a general point of view, what you describe is a perfect example of business purposes, and thus it qualifies for a standard Schengen visa. It does not matter that you will be doing work for your US employer during your trip; anyway, arguably any business visa imples that you do work for your employer. Standard examples of business purposes are visiting a conference or negotiating with a business partner, but this is anyway your work, i.e. something that you do at a request of your employer and what you get paid for. In your case you are going to Germany to collaborate with your colleagues, which is still a perfect business reason for me. Presumably you employer will provide you with documents needed for the embassy so that the embassy will see that there is a business need.
A different case might be if you go to Germany out of your own will (e.g. your US employer is happy with you working remotely from anywhere on Earth, and you choose to spend two months in Germany, a digital nomad type of trip), this is at very least a shady area in modern visa regulations, — but if it is your employer requirement (and the employer will provide you with needed documents), then it is a business case.
Just two things that seem concerning to me.
First, I would not say that you "transfer" to the Germany branch. The word "transfer" may suggest that you will have a new contract with that branch and be paid by that branch, which is really not a business trip, but a full-scale work. However, you say that you'll be still paid by your US branch, so just say that you are going on a business trip to collaborate with your colleagues.
Second, unless you have a specific project to complete, 60 days might seem a bit excessive for just "meeting your colleagues and collaborating". Maybe the visa officer will not mind and a simple letter from your employer will be enough.
Finally, as an US citizen do you need a visa at all? (Although even if you don't need a visa for a business trip, you most probably still need a visa for work, so a distinction between business trip and work is still important.)
Once again, I'm answering from common sense, not from some specific experience, and hope that more knowledgeable users will give more specific answers.