homeassistant

I went through a lot of humidifiers for this exact issue until I landed on this guy. https://a.co/d/d9KsgV5

It's not perfect, but it fit nearly all of my needs (which you listed above). It uses Tyua, so it's not local UNLESS you set it up with LocalTyua like I did. The only major downside is, it beeps every time you have it do something via home assistant. If you're crafty, you could probably remove the speaker, but I haven't bothered (yet).

Here's what I did for humidifiers in my house:

• Dumb, analog-controlled humidifiers (like with the knobs, no digital displays, buttons, modes, etc)
• Local control smart plug (Tasmota flashed Sonoff S31 in my case, but it can be anything)
• Humidity sensor (I use the Zigbee Aqara ones)
• Create a Generic Hygrostat entity

Now you've got a smart humidifier in Home Assistant. You can set the desired humidity, and when the sensor detects it's below this, it'll kick on the smart switch. When it passes the threshold, it'll turn off. It's been great! My humidifiers shut off when the water level drops, so I can even use the power monitoring in the Sonoff switch to send me a "low water" alert when the humidifier should be running, but it's drawing no power!

Remember everyone, clean out your cold humidifiers at least once a month. Otherwise you are literally just spraying mold spores into the air to breathe in. It is linked to respiratory health problems.

They are great, but need to be well cleaned.