The short answer is no.
In December 2020, Clip Studio Paint released CSP Version 1.10.5 and began promoting the ability to import Photoshop brushes in .abr format as part of a major overhaul of the CSP brush engine.
After much testing, we've determined that unfortunately, True Grit Texture Supply brushes will not work satisfactorily once imported into CSP. Results range from, jittery strokes and poor pressure sensitivity to a complete loss of usability. In most cases, the imported brushes do resemble the original brush at all.
Unfortunately, .abr import is a feature that will only work in theory when importing the most simple of brushes (eg just a basic brush tip).
This is also the case with other apps such as Krita, Pixelmator, Gimp, Affinity and Procreate that feature .abr Photoshop brush compatibility. Unfortunately, almost all of our brushes are far too complex to translate properly across multiple brush engines and we spend the time to build our brushes for each platform from scratch to ensure they will always work the best they possibly can on each platform.
Furthermore, our user license agreement covers brushes for use only in the apps they were designed for.