i see now. I believe there has been a misunderstanding in the feature set.
You are setting all the selected meshes to a specific x value on the x axis which means they will sit on the same position as we did for the Y up thing. This feature was for the roads that had different heights to be aligned and same with there x/z axis for the pavements.
What you are wanting is to move all the assets by a select X amount relative to their current position. This is a different way the multi select tool can be used and will require programmed in. This will require a switch for the axis move.
This mode seems like what you would normally expect lol
as before the other feature, the translation tool did not work with multi select.
Hope this helps