MicroWakeWord is a project built on the ESPHome framework.

ESPHome is a project for building, deploying and managing microcontroller firmware (such as ESP32 devices). So, because MicroWakeWord uses ESPHome, you can easily deploy it to your preferred device.

ESPHome is deeply connected inside HomeAssistant and therefore the integration is essentially OOTB - but you have to flash ESPHome firmware on an ESP device which will probably involve soldering electronics. There are some dev kits available that contain everything you need pre-built though (like this one - no endorsement)