The following weapons were used in the film Aquaman:
Colt Model 933
Colt Model 933s are used by Jesse and David Kane's pirates who infiltrate a Russian nuclear submarine.
Ithaca 37 "Stakeout"
An Ithaca 37 "Stakeout" short-barreled shotgun is used by one of Kane's pirates.
One of the pirates is armed with a Glock 17.
M203 Grenade Launcher
One of the pirates is armed with an M933 fitted with an M203 Grenade Launcher. Judging by how it's mounted, it's likely an airsoft version. A similar configuration is used by Jesse Kane (Michael Beach).