Best bowling figures in an innings by Pakistani players on Test debut:

We see that Abrar Ahmed is in 3rd position here, after Mohammad Zahid (1996) and Mohammad Nazir (1969). Most of these bowlers had short Test careers. Perhaps Abrar will fare better. Bilal Asif’s 6-36 is the best for a Pakistani debutant in an away (rather, neutral) Test. Arif Butt’s 6-89 is the best for a Pakistani debutant in an away Test.
We also see the best innings figures by any bowler on Test debut in Pakistan:

Abrar Ahmed is third on this list as well. Also note England’s WG Jacks in the first Test of this series.
After England’s second innings, we look at the revised records for match bowling.
Best match bowling on debut for Pakistan:

Abrar Ahmed’s 11-234 is the second-best for Pakistan, after Mohammad Zahid’s 11-130. We also see that Aizaz Cheema’s 8-103 is the best for a Pakistani debutant in an away Test.
Best match bowling on debut in Pakistan:

Here, too, Abrar comes second after M Zahid. The best performance by a visiting bowler on debut was 6-85 by RMH Cottam in 1969.