Air carrier Dispatcher planned flight unaware of aircraft speed limitation noncompliance with STARs; resulted in need for an FAA exemption.

Narrative

I was planning the event flight and there was a placard I had not seen before; - Left Winglet Lower Blade Removed. Among a FL320 altitude restriction and other performance hits that are handled by Company; the placard requires that the airspeed be limited to 270 KIAS/0.73 Mach or below. I ensured that the flight's speed was restricted per the placard; completed the other normal planning; and released the flight. The Captain called later due to a conflict with the aforementioned placard and the flight's routing. They mentioned that the ZZZZZ2 RNAV STAR they were filed on has a note stating 'Turbojet and turboprop aircraft capable of 280 kt. or greater only.' When I was originally planning the flight I was more focused on ensuring the speed and other performance restrictions were calculated correctly and the thought of the routing having a minimum required speed (compared to a maximum speed limit) did not occur to me. Looking at the other arrivals into ZZZ; the only other procedure that did not have a similar requirement coming from the same direction was the ZZZZZ1 STAR. The Captain requested to be re-released and filed onto the ZZZZZ1; which seemed fine to me during our discussion.I contacted ATC to remove the flight's current filing and was working on re-releasing it until I noticed the note on the ZZZZZ1 stating 'DME/DME/IRU or GPS equipped turbojet aircraft landing ZZZ must file the ZZZZZ3/ZZZZZ4 or ZZZZZ/ZZZZZ5 RNAV STAR.' I contacted the ATC desk to get clarification on whether it would be more appropriate to file the ZZZZZ1 or ZZZZZ2 due to these conflicts and they suggested that they make a request with ATC command center to file the ZZZZZ2 while acknowledging the flight is restricted to 270 KIAS/0.73 Mach or below and FL320 or below due to the placard. The request was approved; and I discussed this plan with the Captain; who agreed. The flight operated without further incident.