Can I run only hots to outdoor safety switch
You have two choices

You either can run all the wires to the switch and then run all the wires from the switch to the appliance (using wire nuts or setscrew splice lugs for the neutral and ground if the switch does not provide neutral and ground bars), or you can run the hots, neutral, and ground to the appliance and then run a 240V switch loop out to the switch where the unswitched hots go out and the switched hots come back.

Given that this is likely larger than a 20A or 30A circuit, and /4 NM isn't available in larger than 10AWG, the better choice is to run all four wires to the switch.  Using bars vs. nuts or setscrew splices is up to you -- just make sure the switch enclosure is properly grounded via a pigtail if you do the latter, though.