Having a belief can be Kfira but not Avoda Zara. As long as I don’t do any of the 4 Avodos or its specific Avoda, I didn’t transgress Avoda Zara.
The Rambam holds that Kishuf is based on the same system as Avoda Zara. Is every Mechashef Oiver on Avoda Zara automatically? It can’t be, since it is not from the Shalosh Aveiros Chamuros and according to the Rashba it is Muttar to heal with Kishuf, and it is Muttar Lihislamed.
This reminds me of a story I recently heard. Once, by a meeting of Rabbanim Reb Aaron called out at someone, “Am Ha’aretz!” The Satmar Rebbe heard this and asked, “Really? He’s an Am Ha’aretz?” Someone there explained to the Satmar Rebbe that Reb Aaron uses ‘Am Ha’aretz’ like the Satmar Rebbe uses Apikores.