Hello Everyone!
Is it possible to connect every smart plug with WiFi+Bluetooth to a USB Bluetooth Antenna - without using WiFi or any Hub?
Everything is nearby and BT should be sufficient. The smart plug should be used for a humidifier. An automation with a nearby sensor send the data for switching on/off humidifier.
In most cases the BT part of the WiFi based plugs and devices is only there for initial setup via your phone unless specifically stated on the product itself that it can be used as an alternate means to control it.
As long as your BT integration is setup in your HA instance and it shows up then you know its able to be used through it once you have it in pairing mode.
Just keep in mind that most BT adapters have a limitation with the max number of devices they can control at any given time, in most cases this is 7 and they have a shorter range as such you want to have BT proxies setup as and where needed.
WiFi and BlueTooth use similar frequencies in the 2.4Ghz range, but the protocols are vastly different. You should be able to apply RF principles to your equipment for appropriate signal boosting/attenuation, but this of often a black art. BlueTooth has device session limitations that are different from WiFi, and the range and connection methods are quite different, by design.
Wait till you discover other transmission technologies such as ZigBee, Thread, LoRa, and even the ESP-NOW protocol. Each solving a different problem, and some more suitable for one than the other.
ESPHome documentation has discussion on using ESP devices to connect HomeAssistant and remote devices and sensors. You may find your solution there.
Thank you for clarification! BT isn't reliable, so I am goin' with G01V3-EU16A (Tasmota ESP32-C3).
That is a very broad statement.
In most scenarios it is deployed, it is the most suitable solution. You may discover situations where it is the most reliable too.