Schlupp lasted the entire duration of the match while Jordan warmed the bench at Vicarage Road.
Second-half substitute Andre Gray scored two minutes after coming on to send Watford into the FA Cup semi-finals.
The Hornets had earlier led through Etienne Capoue's instinctive finish before Michy Batshuayi leveled for the Eagles, finishing coolly after dispossessing Adrian Mariappa.
But soon after replacing Will Hughes, Gray fired past Vincente Guaita to send his club into only their sixth FA Cup semi-final.
Schlupp and Jordan have both been invited by Kwesi Appiah for the final 2019 Africa Cup of Nations qualifier against Kenya in Accra this month.