@buherator for Python code, I like using a combination of ctypes.Structure and hexdump.
https://github.com/alexander-hanel/py-snips/blob/main/readme.py#L372-L404
KaiStruct is also another option https://ide.kaitai.io
@buherator I believe 010 does have that functionality. If you need something free, you can always use McAfee’s old FileInsight. It has a nice feature in which you can select bytes and color code them.