The midfielder is set to sign a three-year deal from Dutch second tier side Heracles Almelo in a deal which is worth six-figures, reportedly as much as €400k.
Kiomourtzoglou, capped twice for Germany at Under-21 level, has featured in all three of his club’s Keuken Kampioen Divisie games this campaign as they have started with three wins from three.
A defensive midfielder, the 24-year-old played over 100 games for SpVgg Unterhaching with over half coming in the third tier of Germany. He then moved to Heracles and has featured 75 times, scoring four goals in the Eredivisie.
Robbie Neilson has been keen to add to his midfield options before the transfer window closes.
With Beni Baningime still out injured and Hearts facing six European games in the Conference League against Fiorentina, Istanbul Başakşehir and RFS greater depth in the squad is required.
Hearts remain in the market for a forward.