According to SportBild (h/t Andy Ha of Football.London), the Gunners will part with a six-figure amount to bring Mislintat to the Emirates Stadium, with the acquisition potentially to be announced next week.
Per the report, Mislintat has been dubbed a "super scout" in the past and has been responsible for Dortmund picking up talent such as Robert Lewandowski, Ousmane Dembele and current forward Pierre Emerick-Aubameyang.
German football journalist Lars Pollmann suggested the departure of the scout represents a substantial blow to the Bundesliga side:
Lars Pollmann @LarsPollmann
Dortmund are suffering colossal brain drain if Mislintat leaves after Tuchel. They didn't get along but two excellent footballing minds.2017-11-15 17:05:32
As noted by Luke Brown of The Independent, the Gunners are on the lookout for a new head of recruitment with their chief scout Steve Rowley set to leave the club. He's been in place since 1996, when Arsene Wenger also took charge of the club.
The same report also relayed that Bayern Munich have tried to pinch Mislintat from their domestic rivals on a number of occasions in the past, while the scout is said to have almost left a year ago when he fell out with former manager Thomas Tuchel.
The work done in the transfer market by Mislintat was key to Dortmund winning back-to-back Bundesliga titles in 2010-11 and 2011-12, as well as their run to the UEFA Champions League final in 2012-13.
Working alongside then-manager Jurgen Klopp, he helped draft in crucial members of the team including Shinji Kagawa, Mats Hummels, Jakub Blaszyczkowski, Neven Subotic and Sven Bender as well as Lewandowski.