[AndrewAction]

On Windows 7 with MC 2019.12.12 and Windows 10 with MC 2020.9 the plugins are found in.
C:\Program Files\Common Files\Avid\Audio\Plug-Ins (the same folder as Pro Tools uses)
The Plug-in Presets use My Documents\Pro Tools\Plug-In Settings\Plug-in Name

I do not have a Mac available with MC at present but I believe it would be the
same file path to the folder you save your presets to from Pro Tools on a Mac.

Andrew

Edit add I believe MC 8.4 was the first version this was available in.