The pins above do not correspond with ESP8285 pins, so we do not know if they are from SPI or HSPI, but they do with the RP2040 pins in the datasheet, see:
Anyway, I think it is irrelevant the pins used in ESP8285, as the firmware there won’t be changed, only pins in RP2040 are meaningful for the purpose of substituting the python image by the basic one.
Regarding AT commands, I found an article here:
which points to this AT command set:
http://room-15.github.io/blog/2015/03/26/esp8266-at-command-reference/