I put factory fog projectors on my 95’ legacy. pulled the wiring switch and harness from a junk yard car. I hooked my fogs as if it was an dealer install because I don’t know how they would act if they were seperate from the headlights.
I believe if you take the yellow/blue wire that comes from the fog switch and connect the yellow blue to the red high beam wire from the headlight running it thru a relay.
haynes has the correct wireing diagram I couldn’t get a good picture or scan so I drew it quick