I wish I could help, but I don't quite understand what USB2SNES is. I'm wanting to assume it's client software for the USB interface on an SD2SNES, but I'm unsure. I'm having a hard time comprehending it because:
https://github.com/saturnu/usb2snes seems to be called USB2SNES, except,
https://krikzz.com/forum/index.php?topi ... 0#msg50820 indicates a guy named RedGuy came along and improved on it, calling it
usb2snesw, based on
this post, which is centred around firmware updating and not so much the debugger (maybe I'm wrong?)
If it is the USB interface to the SD2SNES, then think it's more a question as to whether or not the SD2SNES supports snooping on WRAM regions.
Have you tried contacting
RedGuy directly? Or possibly filing a
GitHub Issue to ask? If not, why not? If so, what'd he say?
You might also try asking Krizz himself, since he's the SD2SNES inventor and could certainly tell you what types of debugger features are possible.
I own an SD2SNES, but I never bothered with the USB interface because I was told it was one of those in-flux-development type of features.
Finally, when you say WRAM, are you talking about:
a) Literal work RAM, i.e. $0000-1FFF of bank $00 (and some other banks (depends on mode 20 vs. 21)),
b) Region $7E0000-7FFFFF as a whole (of which
Item (a) is part of),
c) Battery-backed SRAM (e.g. $6000-7FFF)?
Sadly the acronyms are sometimes misused, so it's always best to clarify.