A humbucker pickup will work with a baritone tuning, but you may want to look at the how much bass the pickup is designed for. Some pickups may work better then others.
I have seen baritones with Duncan Distortions, Duncan JB / ‘59 combos and EMG 81/85 sets from companies like ESP and Schecter. Pickups like the Lace Drop and Gain or DiMarzio D Sonic are both designed for lower frequencies.
I have a Schecter Scorpion with Duncan Distortions, great for hard sounds :headbang1:, not so good for clean.
Hope this helps.