Its not reciprocal lounge access, only works for EI flying on EI metal. Just changing which lounges are offered. No access at EI locations for AA unless in J

Note Sliver status is now no good at ORD (UA refused it in SFO previously)

Access ONLY applies to status holders travelling SFO/ORD to DUB on EI metal, so nothing new there was in place already
Business class passengers will likely need to be on a same day international itinerary including EI (This is basically replacing the exact same agreement that was in place with UA previously) to access lounges elsewhere.

When AA offer access when flying to Charlotte from Dublin to EI status thats reciprocal...