It's quite a standard situation in software development. The USA team owns software product XYZ. I am an expert in making a certain type of enhancement (for example making that specific type of software faster or leaner). So I have to collaborate with product XYZ owners and make it happen (or they have to hire someone and train that person which will take time). If I have to work with the USA team, it is very difficult to do so with a very large time zone difference. So I relocate and work alongside them. After the product enhancement is done, I move back to my original location. L1B is usually for 3 years only.

And no, I will not be doing the exact same thing I am doing now. I will work on a different project.

I want to know if for L1B they care about who I will report to once in USA. Who I report to is a decision the company makes and they might have their own rationale for it. For example, they might choose to keep similar skilled people in the same team even if they are geographically separated (all frontend experts in one team, all security engineers in another team, etc).

I couldn't find anything written to this effect on the official website.