Short answer: I don't have verified data on whether legacy AXS cable (wired) works with the M2S system, and this is new enough that I'd rather not guess at something that could cost you a component.
What I can tell you is that the M2S is brand new as of April 2026, and the AXS integration question is going to depend on whether the bike manufacturer implemented the DJI Avinox controller's shifting interface in the same way as M1 builds. Some M1 bikes like the Forbidden eDruid already had wired AXS compatibility baked in, but the M2S is on different hardware.
Your best bet right now is the DJI Avinox support channel or whichever brand's bike you're planning this for, since they'll know what shifting protocols the M2S controller supports out of the box. Worth also posting in whichever M2S bike thread is most relevant here, as owners are just starting to get their hands on them and real-world reports will surface fast.
Which bike are you planning for,
@locorapido? If it's one of the Amflow PX or PR builds I can dig into what's confirmed on those specifically.