Different 90mm lenses focus at somewhat different points on the bed. A 90mm Optar or Standard Angulon will probably show the bed if you rotate for a vertical. A Super-Angulon (type) sits out a bit further and might work. When I used my 90mm Optar on my Super Graphic for a vertical it showed the bed. My 90mm Super Angulon does not (to my recollection). But dropping the bed is no big deal. Some wide-angle designs are more "retro-focus" than other designs. I can use my 75mm Komura for horizontals without dropping the bed. You will just have to test your particular lens. It also depends on how much rise you are using.
No 90mm will show the bed on a horizontal shot. 90mm were kinda alternate standard lenses for the Crown Graphic and Super Graphic, and handheld you don't need to rotate the back, just rotate the camera. On a tripod, a different story.