You can check this tutorial on how I made them:
To import a tool into your Clip Studio Paint Program:
1. Download and Unzip the Zip.Folder.
2. Open Clip Studio Paint and right-click on one of your brushes (doesn't matter which one).
3. Select 'Import Sub Tool...' and go to the unzipped brushes in your directory.
4. Chose the brush you want to import and press okay. It will create a new brush with the imported setting.
5. Try it out and enjoy~
No need to give credit when using these brushes but please do NOT reupload anywhere or claim as your own!!
My Basic Brushes for Clip Studio:
These, no. You can however get the tip from the brush and place it on a canvas with black then fill the blank space you want colored with white. If you set the layer setting to greyscale, you can make a new brush and switch the black and white color for foreground and background color. If you want them to be already colored, shade the white part and make sure it loops, then save the brush tip in color layer mode.