Light channels with ray-tracing don’t seem to be currently supported, no.
However, NVIDIA has a fork of the UE4 editor that supports this feature (along with other ray-tracing improvements) called RTX-dev. It is currently unknown if the UE4 developers intend to integrate these changes into the stock editor.
The RTX-dev link is available here (you must have your Epic Games and GitHub account linked to access it, as it is a private repo), and the NVIDIA documentation is available here.
Hope this helps!