I've have found a way to access my drawings! (it's a bit unorthodox tho...) First, make a workshop item with all of the drawings you want, and then add it to your collection (hit the subscribe button!).

btw im on windows so i don't know what will work on other devices

Next you are going to have access stream Storage in your files where they store all of there local game data. If you don't know how just right click any game you have installed on your computer and hover over "Manage" and then click on "Browse local files".
(post writing note : I find this method the easiest for file manipulation. if there are other easier ways then please tell! :) )

Once FileExplorer has opened, go to the "steamapps" folder then the "Workshop" folder. once there you will see folders which has all of your workshop stuff in it (i know it looks like a bunch of numbers but trust me). Next 'simply' find the Sketch Crawler 's workshop folder and boom there are your drawings!

I think your next best option would be to go to the %appdata% folder as follows = AppData>LocalLow>Koan>SketchCrawler>account>skins and there will be a couple of folders to navigate which contain said drawings! If you edit and save them there you'll replace the image ingame too so beware of that! So always make a backup just in case!