I didn’t mean that you shouldn’t make those rotated glyphs. But at least for the Latin part it is not needed.
And I just checked. If the glyph has a suffix “.rotat”, “.vert” or “.vrt2” and contains a component that is rotated by 90° the automatic alignment will position the component and set the vertWidth correctly.
For Mongolian it is a totally different matter. All rendering engines expect the glyphs to be rotated 90° and will rotate the whole line from Left-To-Right to vertical. Glyph could build proper vertical Mongolian fonts.