Ok, i found some alternatives of import/export and deleting for users.
Find hided folder "C:\Users\user_name\AppData\LocalLow\Sebastian Lague\Digital Logic Sim\SaveData" to find all projects (chips are included in them). You can delete/copy this files to any projects you want. Also you can download projects/chips from other users and paste them to that folder. Simpler than i thinked.