How do you load programs into RAM of an ESP32 IC, not WROVER/WROOM module?

[zliudr]

I've used WROVER for a number of years with ESP-IDF, micropython, and sometimes arduino IDE so I'm familiar with its FLASH partitions and PSRAM etc. But I am wondering, if I use an ESP32-S2, the bare IC, not a module with PSRAM, FLASH, antenna, as a USB OTG host for instance, since it's so much cheaper than a MAX3421e, how do I go about loading its firmware into its RAM? I know that esptool can load stub into ESP32 so I wonder if that means you can send a program's binary to an ESP32 IC via some protocol. So if I can implement this protocol, and probably toggle some pins to reset ESP32-S2, I can have my main MCU send the firmware to ESP32-S2?

[ESP_Sprite]

There's the equivalent of esptool in C library form here but I'm not 100% sure if it has the API to upload to RAM and execute from there. Regardless, it does implement the API itself, so it probably would be a nice starting point. Would be great if you documented this if you can get it to work!