After doing some reading of the rules and latest errata, I realized that there is nothing said at all about battle armor active probes and C3 being incompatible with BA stealth armor.
I know that mech and vehicle stealth armor both render active probes useless when active because of the self-ECM effect. I did see an open issue of this forum that was unanswered that pointed out that the void signature system as it is in current errata can use active probes, but null sig deactivates active probes (except Nova CEWS).
https://bg.battletech.com/forums/index.php?topic=84709.msg2004407#msg2004407Back to battle armor, I have checked every single reference of BA stealth and mimetic armor in every book from TW, TO:AU&E, TO:AR, and TM, and the latest errata for them all, and there is no mention at all of any effect on an active probe or c3 mounted in the unit. I also checked every reference to BA mounted active probes and c3, again no mention any effect by being mounted in a suit with stealth armor.
Are BA active probes and C3 working in stealth BAs intended? If so, they make for a pretty great scout unit.