I created a mod over a year ago which is used by the vast majority of the community, and seeing as there is an official addons forum, I decided to upload and explain it here. My mod can be found on CurseForge by clicking here.
I will try to update this mod as soon as a new update drops for Mine Mine no Mi that causes conflicts with Haki Bar.
hakibar-common.toml
You can configure how many ticks it takes for everybody's haki overuse values to update by modifying the "Throttle" variable. The lowest throttle (which is the default) is 1 tick. For reference, there is 20 ticks in a second.
hakibar-client.toml
In the client config you will see a Fill Hud, Container Hud, and a Overuse Hud. These 3 settings have 3 different options to control the X, Y, and Z axis.
The Container Hud is the border, the Fill Hud is the inner colour which will shrink and grow depending on your remaining haki, and Overuse Hud is the text specifying your current overuse out of your max overuse.