Matter Graph?

Exactly! @bill.d just posted about the SMHUB, a new offering from SMLIGHT.

The SMHub uses a CC26xx for the zigbee radio and an EFR32xx for the Thread radio. Memory says that the C-8 and C-8 Pro have an EFR32xx radio currently used for zigbee. So I think it should be possible to repurpose it as a Thread radio.