Thanks for this discussion! Along with:
it helped me work out the # syntax for branches. comment#8 here seems a bit harder than using my published branch to the fork I made of
lib_deps =
fastled/FastLED
Wire
adafruit/Adafruit BusIO
adafruit/Adafruit GFX Library
;https://github.com/mrfaptastic/ESP32-HUB75-MatrixPanel-I2S-DMA.git
https://github.com/jdeltoft/ESP32-HUB75-MatrixPanel-DMA#fix_offset_for_chain_top_right_down