As I'm the one who originally wrote this page back when I was still a staff member, I'd like to emphasize one specific point:

(Which ScottyDog did by creating this thread.)

I'm no longer a ServerAdmin, thus I will not give my opinion on whether those mods are legal on ECC. (I'll leave that to Nicit and the rest of the staff team.) However, I'll comment on the technical side and whether the specific mods mentioned would actually work:

"Middle-click sorting" sounds like it messes with multiple item stacks at once, there's a good chance anticheat won't like it and will kick you every time you attempt to use it.

I did some research regarding "vein mining", and the only mod I could find is a server plugin with an associated client mod (which, however, doesn't work without the plugin when used in multiplayer). Which makes sense, considering that breaking multiple blocks at the same time edits the world in a non-vanilla way. If there were/is a client-only mod, anticheat would probably kick you for it (because breaking multiple blocks at the same time is obviously not normal).


TL;DR: If the staff team allows it, you can use such mods. But I don't think anticheat would let you use them.