This data-pack will add a warning system to your server world. You can use /function servertools:help to get more info. To uninstall this datapack make sure you open up settings and run the uninstall command before you remove it from the world folder

Use /function servertools:settings to open up the command list
Use /function srvertools:version if you need to know the version your running
Use select to select the nearest player alternatively you can use /team join <playername> selected (ONLY DO THIS TO ONE PLAYER)
Use deselect to deselect that player
Use add/remove in warnings limit to change the number of warnings it takes to get banned
Use add/remove in player warnings to change the number of warnings the selected player has
use show/hide to hide or show the scoreboard (default off)
Use unbanish to unbanish the selected player (they will lose their items and be on 1 warning less than the warning limit)
Uninstall datapack uninstalls the datapack so that you can safetly remove it from the world folder

All players who reach this limit automatically go into spectator and get teleported to 0, -60, 0 with a banished message for eternity even if they log out/in. They can't do anything so they are basically banned lus datapacks can't use /ban so yea it's a work around. You can use unbanish to unbanish the selected player [​from the settings panel] (they will lose their items and be on 1 warning less than the warning limit)