If anyone is going to do it I highly recommend just going with esphome now for the firmware, it’s way simpler and better maintained. You can even update the firmware over the network.
And if you want to turn your ESP8266 into a standalone appliance, with a web interface and directly editable config that doesn't need a build step, Tasmota is another great option.
How on EARTH did I not know esphome existed?! Why am I bothering with this heterogeneous plate of home coded ESP and Arduino spaghetti throughout my house?!
A simple pir sensor just has a digital out that is either high or low. That is supported as a digital in sensor. Only for devices with a more complicated protocol (mostly i2c, spi and uart) you need a special sensor specific integration
If you install Home Assistant (HAOS or Supervised) on something then ESPHome is a one click install with a web GUI. There's an OVA for HAOS as well as all the usual suspects - amd_64, RPi and more.
If you don't want all that stuff then do it from the command prompt, most Linux distros have it in the package manager and no doubt Mac n that have easy to install options.
https://tasmota.github.io/docs/