You can find your saved blueprints in the mod folder.
In singleplayer or if you are the host of a co-op world it will be in

If you are on a multiplayer server then only the host will be able to delete it by opening the mod folder and deleting the blueprint file.

引用自 Nefar1on：

You can find your saved blueprints in the mod folder.
In singleplayer or if you are the host of a co-op world it will be in

...steamapps\workshop\content\366090\2378050704\Blueprints

If you are on a multiplayer server then only the host will be able to delete it by opening the mod folder and deleting the blueprint file.

...steamapps\common\Colony Survival\gamedata\mods\Expanded Construction\Blueprints

i searched in my gamefiles folder for blueprints and found nothing tho