This just loads mods (.so files) from /sdcard/Android/data/com.beatgames.beatsaber/files/mods/ and includes some examples for function hooking.
Uses https://github.com/ele7enxxh/Android-Inline-Hook + some macros for magic
Follow https://koz.io/using-frida-on-android-without-root/ to learn how to inject the modloader-library into the beatsaber apk (with the so built from this instead of frida) or just use BeatOn.
The function offsets (as well as infos about the structs) can be obtained with il2cppdumper
ndk-build NDK_PROJECT_PATH=. APP_BUILD_SCRIPT=./Android.mk NDK_APPLICATION_MK=./Application.mk