Answer
Yes, a foreign vaccination certificate can be used if its information is legible and it undergoes the required validation in Uruguay. You will usually need the original or a high-quality copy, a Spanish translation in the requested format, and clear dates, vaccine names, and personal details.
Do not repeat vaccinations simply because an old card was issued in another country. First, show it to a medical facility: a doctor or authorized staff member will determine which records can be accepted and which need to be restored or supplemented.
It is best to save the electronic certificate together with the QR code and a means of verification. A screenshot from an app is less useful than a file with verifiable data. After validation, you can obtain Uruguayan confirmation that can be used for subsequent administrative procedures.