Spartak, the only difference is the Walther PPQ Q5 model 2837218 has the Magazine Release on the Trigger Guard and the PPQ Q5 model 2813335 has the standard Magazine Release Button behind the Trigger Guard. Personal preference as to which you like better.

here is a article on the lever release shootingillustrated.com/articles/2019/4/11/new-for-2019-walther-arms-ppq-q4-tac-m1-q5-match-m1/

the 2837218 has the Q5 MATCH M1 (Lever Magazine Release) the 2813335 has the mag release button behind the trigger guard see the models here waltherarms.com/handguns/q5-match/

Spartak, I'm not finding any feature differences. Walther Customer Service may be able to shed some light at 479-242-8500 EXT. 507