Fiskekake

I'm by no means an expert, and I'm not sure what API keys you are referring to. I know that Tuya smart devices usually have two versions, a wifi and a Zigbee one. The wifi ones require you to add them using a terrible smartphone app, and the integration with Home assistant sucks. The Zigbee ones work like any other zigbee device, locally controlled. I have several Tuya Zigbee devices which works great, they are integrated in home assistant using zigbee2mqtt.

I have some cheap ass Tuya Zigbee sensors from AliExpress. In my experience they are reliable, quite small, i sill haven't changed the battery, and they are super cheap. Make sure you get the Zigbee ones, not the wifi version.