What is the easiest way to write text in isometric view so that it is horizontal ?
Using TTF with a different z/b and z/h so the text is '3D', type your wording in plan, then:
Option 1 - use the 3D Menu/Explode/TTF to slab, then in an elevation view, rotate or mirror to 'stand up' the text. This method is okay if you don't require to edit the text and change the wording as it will need to be repeated from the start,
Option 2 - save the TTF text as a symbol, reinsert back into the drawing and rotate/mirror to 'stand up' the text.