There is an open config API for Forge & Fabric called ClothConfigAPI. It's a mod that allows for easier creation of config screens, sort of what Forge had by default in 1.12.2-. Would you guys be able to use this to create a graphical config instead of having to rely on purely editing a config file for 1.16.5?

https://www.curseforge.com/minecraft/mc-mods/cloth-config-forge