I have dual nationality; let's say country A and country B. I am traveling to a third country, country X. I have previously used passport A to visit country X. On my next visit I want to use passport B to enter country X instead. Will this be a problem?
Countries B and X are both in the European Union, but country A is not. I want to work in country X, so using passport B is much better than passport A, since I don't need a work visa. The reason I used passport A previously is that I did not have a valid passport B at the time (I have never actually lived in country B).
I want this to be a general question, but to be specific X=United Kingdom, B=Germany, and A=United States. There are other questions on this site that deal with traveling between A and B in my situation, but I am visiting a third country and am worried about being inconsistent with my passport use.