that UK Bromton guy SP Cuts and modifies the steering mast to use a telescopic suspension seatpost to mount the handlebars ..
Clever Yank framebuilders can likely do similar..
thing is you lengthen the hub to fork crown difference, to have suspension travel, the finely tuned handling gets messed up.

Yea Pan Tour hubs for folders only move a half inch , may help riding chipseal roads though..