XLMMacroDeobfuscator can be used to decode obfuscated XLM macros (also known as Excel 4.0 macros). It utilizes an internal XLM emulator to interpret the macros, without fully performing the code.
It supports both xls, xlsm, and xlsb formats.
It uses xlrd2, pyxlsb2 and its own parser to extract cells and other information from xls, xlsb and xlsm files, respectively.
You can also find XLM grammar in xlm-macro-lark.template