Nuki & Ekey


I have already a existing Fingerprint from company Ekey (SE 2 Reg) and now I want to Upgrade with a Nuki. The Problem is Ekey doesn’t have a Bluetooth connection, only 2 relais. In a other topic I read the posibillity of using a FOB?
Is there a different solution available?
If not, what are the specifications/requirements to the Relais?
Thanks for the help.

Best regards Andi