I've been looking at the inscriptions on the weapons that are available in the pre-order version for a long time and tried to decipher them, but thanks to friends, I finally realized what was written
On a white weapon (refers to OTG 41) - Price's phrase from the dialogue with Gas at MW19:
«You draw the line wherever you need, Sergeant. End of the day someone has to make the enemy scared of the dark. We get dirty and the world stays clean. That's the mission.»
On a black weapon with a red border in Russian (Konni Group ) - Makarov 's monologue in the Konni hangar from MW23:
«Боевые товарищи, я был далеко, но я всегда был с вами.<…> Это бой за восприятие (мировоззрение). Ложь всегда летит там, где правда ползёт. Управляя мнениями, управляешь миром… Это - наше оружие! Мы используем его в войне.»
The text of Makarov's phrase is taken from the official Russian localization of the game.