Not sure if this has been covered in here or not, but I did find a fairly simple and easy to setup solution this past week. I ordered one of the many Smart Oil Diffusers on amazon that specifically said they worked with Tuya/Smart Life. Once I got the diffuser I setup a Smart Life account and added the device to it. I then used the Tuya integration in Home Assistant and during the setup process I told it I was a Smart Life user. Initially, I noticed that no device was available for the diffuser in home assistant. However, I quickly found a work around for this. In the Smart Life app, simply make a Tap-To-Run automation that turns on and sets the spray volume and/or led light and save it. Then reboot your Home Assistant and you should find that a new scene has been pulled in from Tuya which you can activate in an automation within Home Assistant. I created a scene for Master Bedroom Diffuser Full Spray, Partial Spray and Off. Very simple setup and several diffusers meet the criteria. Just look for the ones that say the app they use is Smart Life or Tuya!
Model I purchased and confirm working: https://www.amazon.com/gp/product/B07M6QD7LN/