The Borchardt C-93 is seen as the main sidearm of Lieutenant Tsurumi again in the season.
Mauser C96
The Mauser C96 is seen with Toni Anji as his main sidearm, first seen in "Blue Eyes".
Nambu 1902
The Nambu 1902 is first seen in "Fakes" with Superior Private Hyakunosuke Ogata before he's disarmed by Sergeant Hajime Tsukishima. Sugimoto uses it before it was taken by Lt. Col. Yodogawa in "Into the Belly".
Revolvers
Smith & Wesson Model 10
The Smith & Wesson Model 10 is used by an armed civilian traveling at the end of "Blue Eyes".
Type 26 Revolver
The Type 26 Revolver is used by 2nd Lt. Koito Otonoshin in "Into the Belly".
Battle Rifles
Arisaka Type 30
The Arisaka Type 30 is seen with Imperial Japanese Army soldiers throughout the second season, among them including Saichi Sugimoto aka "Immortal Sugimoto" and soldiers of the 7th Infantry Division. Some Imperial Police Bureau officers use them seemingly.
Arisaka Type 38
An Arisaka Type 38 is seen first in "The Great Plan to Infiltrate the Asahikawa 7th Division!!" when the rifle was present to Tsurumi and Tsukishima by Lt. Gen. Narizou Arisaka.
Mosin Nagant M1891
The Mosin Nagant M1891 is seen with Imperial Russian Army forces during the Siege of Port Arthur in "Ani Nekko". Some are also used by guards at Abashiri Prison; these are presumably captured war materiel from the Russo-Japanese War.
Murata Rifle
The Murata Rifle is seen with Tanigaki in the season, using it as his main weapon. Matagi hunters are seen with the Murata, being a traditional weapon.
Carbines
Spencer 1860 Carbine
The Spencer 1860 Carbine is seen in "Kamuy Hopunire" when Ogata explains his backstory.
Winchester Model 1892
The Winchester Model 1892 returns in the second season with Hijikata, which he uses it as his main weapon.
A Prosthetic leg modded to fire shotgun-based buckshot rounds is presented to Kouhei Nikaido to replace his lost leg in "The Great Plan to Infiltrate the Asahikawa 7th Division!!".
Winchester Model 1897
A Winchester Model 1897 can be seen in "Everybody, Get Together! It's a Murder Hotel!" in the Minai Guns and Gunpowder Shop. Tsurumi uses it in the siege of Abashiri Prison in "Overwhelmed".
Machine Guns
Maxim 1895
The Maxim 1895 is seen with Abashiri Prison security forces during the siege in "Overwhelmed".
Type 38 Machine Gun
The Type 38 machine gun is seen in "The Great Plan to Infiltrate the Asahikawa 7th Division!!" when Arisaka presented it to Tsurumi. The 71D tests it in combat in the Abashiri Prison siege, first seen in "Overwhelmed".
Grenades
Homemade Grenade
Some homemade grenades based on ingredients purchased from Minai Guns and Gunpowder Shop are used by Kiroranke uses it in "Overwhelmed" during the siege at Abashiri Prison.
IRA Grenade
7ID Grenade
Others
Bow
An Ainu-made bow is used throughout the anime by Asirpa as her main weapon in the second season.