I've since had time to package this up a bit better so the component is now available on github at https://github.com/trvrnrth/esphome-bsec-bme680
Of most note is that it no longer relies on a patched arduino framework for ESP8266 boards and instead makes use of a re-packaged libalgobsec.a library which makes the entire setup much easier. This was described at https://community.bosch-sensortec.com/t5/MEMS-sensors-forum/BSEC-library-installation-instructions-f... and I have also PRed those changes at https://github.com/BoschSensortec/BSEC-Arduino-library/pull/51 for review.
I've just realized, that most of your code is writen in python. I'm moving most of my sensors to MicroPython but I'm struggeling with the BME680 (the BSEC C++ code side). Can you provide some pointers on how you integrated the BSEC library into your python code? Or maybe repurpose your code for MicroPython too? I'm sure the community there would highly appreciate it (I'm just a python beginner).
The python you see is for the ESPHome code generation framework. The actual sensor handling is still C++. I'm afraid I've not touched MicroPython so can't really help you out there.