Why draw in Adobe Illustrator if it's already sketched in Procreate? Here are my thoughts...
Procreate is a bitmap file format while Illustrator is vector. The advantage of vector is it’s easily manipulated (easy to make changes and updates), smaller file size, and has an infinite resolution. Plus I find it easier to add construction details like stitching and closures in Illustrator. Although, you could also use a stitching brush in Procreate. .