I would think it would be very difficult to sell in the EU without a QMS (unless I'm misunderstanding and you wouldn't legally be considered the manufacturer). Per
EU MDR:
"The manufacturer shall establish, document and implement a quality management system as described in Article 10(9) and maintain its effectiveness throughout the life cycle of the devices concerned."
"‘manufacturer’ means a natural or legal person who manufactures or fully refurbishes a device or has a device designed, manufactured or fully refurbished, and markets that device under its name or trade mark;"
And from the
European Medicines Agency:
"Manufacturers can place a CE (Conformité Européenne) mark on a medical device once it has passed a conformity assessment.
"The conformity assessment
usually involves an audit of the manufacturer's quality system and, depending on the type of device, a review of technical documentation from the manufacturer on the safety and performance of the device."
Emphasis mine.