The main idea, that assembler is always the same.
All ULP cores have one esp32ulp-parse.y file that must be updated if new commands added.
This file will be converted to the *.c file and will be linkedd to the project.
For each assembler command in common tc-esp32ulp_common.c file the processing function (command function) will be called.
Inside of the command function the switch have to shoose the target core.

To include new ULP core to the binutils, please follow the next steps:

1. In file tc-esp32ulp in md_parse_option() define your ULP version.
2. Add new instructions into esp32ulp-parse.y and esp32ulp-lex.l files.
3. Add new files with instructions processing into the project in the same way as tc-esp32ulp_esp32.c (just search text tc-esp32ulp_esp32.).
4. Add mew command processing into the elf32-esp32ulp.c and not forget to increase ESP32ULP_RELOC_MAX
...