Probably You could port MultiWii to ESP32

[kostyamat]

To get a good start, you could port MultiWii firmware to your platform. It has not developed for a long time, but it will allow to connect more people who are interested in ESP32, but who continue to use the Arduino IDE, and do not want to move to complex console compilers. And to include more developers in the development, you could share the wiring diagram of the standard NodeMCU ESP32, and sensors such as GY-86, as is done on your project.

[michprev]

Currently I am working on a custom SDK for ESP32 without FreeRTOS (or at least a subset with SPI and I2C drivers). That will probably take a lot of time. After that I would like to rewrite this code to run on my SDK.

I do not plan to support Arduino IDE. It is not that hard to compile the program from a console.