I have 9yrs embedded software experience, and I worked on language tools chain, including assembler, compiler, linker, debugger, simulator, ide, for 8-bit, 16-bit cisc/risc MCUs.
This project would include implementation of a lexer, an instruction set, an assembler, and a linker( bin converter). The project does not need complex functionalities, however, we still need separate these parts to achieve a clearly structured final project. In case you might need to extend it in future.
I can do the Simulator part as well.
The project will be done in C++ or Java.