Seeing as the distance between the shift lever pivot and the gear fork rod are fixed, a shorter rod is not possible. There is some adjustment in the pedal linkage to move the lever end up or down to suit your boot toe.
I think you mean a quickshifter that momentarily cuts thr engine and allows clutchless shifts up and down through the gearbox. This uses the same length rod but has a load cell at one or both ends that detect pressure, then send a signal to the ecu to cut ignition for a split second. Do a search on here. This has been covered before. There are aftermarket and genuine ones available, and the latter only allows clutchless up shifts.
With practice, you can shift very smoothly and quickly, provided your clutch is working well and staying above 3000rpm, higher rpm is even better
