The Slot.it Type C universal chip is compatible with oXigen, Scalextric Digital and Carrera Digital. A change of firmware is required to switch between each system.
Scorpius announced in June 2020 that the future Scorpius Generation II decoder will be automatically compatible with Scorpius, oXigen, Scalextric, Carrera, SCX Advance and Ninco N-Digital. The chip has not been released yet - and I've yet to see an explanation of how the chip will work with the SCX Advance and Ninco systems, which are very different from the other four in terms of lane-changing and lap counting.