Want to try this out

[Soulfire3k]

How do I add this to my game using Dalamud? I can't seem to find a Plugin Repository link that works.

[JazzyByDefalt]

Not sure if there's a working repo link but you can install the plugin through Dalamud itself:

Launch ffxiv, and use /xlplugins to open the Plugin Installer. Click settings in the bottom right then go to the experimental tab, at the very top is a check box for "Get plugin testing builds". Check this and hit save. Exit settings.

From the Plugin Installer, the "All Plugins" drop-down will now contain a new list called "Testing Available". This list contains the High FPS Physics Fix plugin. Click on it and hit install like you would a regular plugin.