In case the companies use procurean, they still will need to sign the paper documents, or electronic versions will be just fine?
No, one of the main goals of Procurean network is to remove trade barriers between participating businesses and lower transaction costs to a minimum. Procurean will generate and exchange documents in accordance with GS1 standards between participating parties. Businesses can choose to exchange paper documents additionally, but this won't be needed. Document storage will also be reinforced with blockchain technology.
That's a great news. The documentation often requires a whole department of workers, and it's too heavy for the small companies to handle.