Unfortunately, our products experts can't obtain this information. I advise you to contact Swisscom directly or the brand. ):

The operating instructions for the repeater state: DECT standard compatible: https://gse.gigaset.com/fileadmin/gigaset/images/CustomerCare/Manuals/Repeater/Repeater_HX/A31008-N603-R101-1-SU19_02-04-2019_ba.pdf So it should work with any DECT handset. Many greetings

No, that is not possible.

Compatible with DECT / CAT-iq routers that support the new repeater standard ETS300700 V2.1.1 (VoIP, encryption, call forwarding) * (possible functional restrictions, e.g. with encryption) Compatible with all DECT routers * (functional restrictions possible, e.g. with encryption) All Gigaset handsets fully support HX repeater operation. Full repeater compatibility and - expandable up to 6 HX repeaters: Gigaset DX800A all-in-one Gigaset DL500A - expandable to 2 HX repeaters: Gigaset analogue base stations of the C / S / SL class Gigaset GO systems (GO Box 100) Gigaset IP systems, e.g. C430IP / C530IP, Backwards compatible with other Gigaset devices that support a DECT repeater (with Repeater 1.0 - Range Extension functionality): Class A base stations, E560 / E560A base stations.