Clarifying what you are asking. You want to place images in a folder in your hard disk and point to them from Tiddlywiki, so that images will be shown in Tiddlywiki without being actually embedded in the file? If that is the case, yes it is possible. See the following link.
https://tiddlywiki.com/#ExternalImages
Feel free to ask things you can't figure out.
Sincerely
Riz
https://ibnishak.github.io/Timimi/