Hi there! Welcome to the forum!
Actually I myself have trouble knowing their english counterpart. But by glancing through the Unit Info (when buying my troops) I can tell exactly what unit that is. You can see the unit class/type just below that unit's native name on the buy screen. So, if you see a Spaehtrupp on the Unit Info, you can just see below it that it is a scout type unit. But this won't do if you're looking for a formation's English name, for example, you won't find the english name in the buy screen for a company formation called SturmPionierKp, this you need to see the individual units to know what that formation is actually.
Also, when you're mid battle, you can see the unit type/class of a given formation by pressing the H button for headquarter roster screen. You can find it on the middle and right part of the screen where the units & subordinates are listed.
Cheers!
RightDeve