Exported? Dont you mean "imported"?
First question- did you import your brushes from somewhere? Or did you use the [Clip Studio] Assets and download brushes from there? If you used the assets, the brushes might be in the materials section under "downloads".
As for actual imported brushes from elsewhere, I transferred my fave brushes over to iPad CSP using Dropbox; just loaded the brushes on Dropbox on my laptop- then opened CSP on my iPad & imported the brushes in from my Dropbox on my iPad...