Advice for identifying functions and their arguments within a C++ exe

[gurrenm3]

Hello, I want to use Iced on a C++ game executable to identify all of the functions in the game and their arguments. The purpose is to create a modding API that allows 3rd party developers to make new content for their favorite games. I've traditionally used IDA for it but would like to find a solution that is free and easier for end users to use.