If you’re going to be doing any amount of soldering, I’d highly suggest the Hakko FX888D. You want to use a good iron, otherwise you’ll get poor results and/or be more likely to hurt yourself. (Hitting one’s thumb with a hot soldering iron is not fun.)
Sadly it can’t work that way. From a programming perspective alone they are very different engines.
Unity uses C# while Unreal is C++.