Hey there! Unfortunately I can't really directly answer this question since I use Paint Tool Sai and the brushes I use are self-made, but maybe searching for a "dry brush" and "square paint brush" would yield results similar to the ones I use... I use those two, and then just the usual airbrush from time to time. Oh, and the manga-style art is just drawn with a regular round brush and overlayed halftone textures.