I wanted to make a custom Cog class with the CogMeta supposingly existing in discord.ext.commands, but when I do discord.ext.commands.CogMeta it error AttributeError: module 'discord.ext.commands' has no attribute 'CogMeta'. Am I missing something?
When checking the docs linked in the question, looking at version master, the CogMeta class is discord.cog.CogMeta, as opposed to on version stable, where it is discord.ext.commands.CogMeta as you assumed. So probably you are using the master version rather than the stable version.
Link to master version: https://docs.pycord.dev/en/master/ext/commands/api.html#cogmeta
Link to stable version: https://docs.pycord.dev/en/stable/ext/commands/api.html#cogmeta