Either a separate mod or an option in nametags mod, when enabled, depending on the server you're on it'll give you options to select the mode you want to show tiers in. When you select a mode, if someone has tier tested in that mode you picked then it'll show up in their nametag. For example: "S | xFlxme". It doesn't need to be an extra mod and could easily be apart of the level head mod.
We have developers who can easily develop this mod and make it compatible with Lunar Client. This would be a great addition to Lunar Client because users could use this to identify the skill level of different users and people can flex their tiers that they worked so hard to get.
For those who don't know what tier testing, you basically get ranked based on how you play in a 1v1 against another player. It's done on servers such as Hypixel, Minemen Club, or Bridge Scrims.
Anything like the image below would work except it'd obviously look good and well-made.
It'll work with our Discord tier list server with over 5.6k members. If any of those from Lunar Client see this and are interested. DM me for our Discord's link.