Here are two of my favorite sketch brushes for Procreate: The SKETCH BRUSH and the BLANK OUTLINER.
Pen pressure controls opacity and size
Tilt controls size
Speed controls opacity and size
To celebrate the awesome 3.2 update of Procreate I'm giving them away for FREE. If you want to support my work, please consider making a small donation (pay what you want option). Thank you! If you like the sketch brushes, check out my other brush sets too: https://sellfy.com/georgvw