skyui VS skyui.plugins

Grab the SkyUI sources here, for other mods they are usually includes with the download or on the Nexus.

This is a better link than the one I originally gave. I'm going to edit my original reply to use that link. I verified that the download works for SkyUI SDK 5.1 which is probably the version you need.

SkyUI SDK on Github, includes some example scripts.

4) Open the SkyUI translation file (with the same language) from https://github.com/schlangster/skyui/tree/master/dist/Data/Interface/Translations (click on the file name, click on the Raw button)

This won't help you, but I'd like to mention anyway that the MCM has key conflict detection support built into it, but it has be setup by the mod author when they're creating their MCM. If everyone did this correctly, you wouldn't have this problem. Key Conflict Management is discussed in the MCM Advanced Features.

You need the skyui sdk it contains ski configbase

Assuming you have covered the ground for basic Papyrus scripting, there is the MCM API documentation which covers regular implementation of an MCM, including standard examples.

Are you a mod author interested in using MCM? The Documentation explains how it works.

A great tutorial for making MCMs is here. Without that I never would have figured out how to do it. You'll also need the SkyUI SDK which I think you can find here. Just make sure it's the right version for your installation of SkyUI.