Germany:
Infantry: Walther 9mm P-38
Mauser 7,92mm wz.98
Machine gun 7,92mm wz.1934 MG-34
Anti tank rifle 7,62mm PzB-39 wz.1939
Panzer (mobile units):
PzKpfw Pz-35(t)
PzKpfw Pz-38(t) Ausf.A
PzKpfw Pz-I Ausf. B
PzKpfw Pz-II Ausf. C
PzKpfw Pz-III Aufs. A-E
PzKpfw Pz-IV Aufs. A-C
PzKpfw ADGZ
SdKfz 221
SdKfz 222
SdKfz 231 8-Rad
SdKfz 7 (and all models from 7-11)
SdKfz 251/1 Ausf. A
Luftwaffe (German Airforce)
Messerschmitt Me109 (E and D)
Arado Ar 68
Messerschmitt Me 110
Junkers Ju 87B Stuka
Henschel He 111B
(and lots of other type of aircrafts ;p)

Russia
Infantry: (sorry couldn't find much about that)
Tanks: T-26
T-37
T-38
BT-2
BT-5
BT-7
T-28
(and few of others)

Poland
Infantry:
9mm wz. 35 "Vis"
Pistolet maszynowy 9mm wz. 38 "Mors''
Karabin 7,92mm wz. 98 i wz. 98a "Mauser''
Karabinek 7,92mm wz. 98 "Mauser" PWU
Karabinek 7,92mm wz. 29
Karabinek 7,92mm wz. 91/98/23 "Mosin"
Karabinek 7,92mm wz. 91/98/25 "Mosin"
Karabin 8mm wz. 1886/93 "Lebel"
Karabin 8mm wz. 1916 "Berthier"
Karabin 8mm wz. 1895 "Mannlicher"
Karabinek 11mm wz. 1873/77 "Werndl"
Karabin samopowtarzalny 7,92mm wz. 38M
Rkm 7,92mm wz. 28 "Browning"
Rkm 7,92mm wz. 15 "Chauchat"
Rkm 7,92mm wz. 1915 "Bergmann"
Lkm 7,92mm wz. 08/15 "Maxim"
Ckm 7,92mm wz. 08 "Maxim"
Ckm 7,92mm wz. 14 "Hotchkiss"
Ckm 7,92mm wz. 30 "Browning"
Nkm 13,2mm wz. 30 "Hotchkiss"
Karabin ppanc 7,92 mm wz. 35 "Kb.Ur." (Anti tank rifle)
Air-force
PZL P-7a
PZL P-11c
PZL 23b karas
PZL 37b Los

Cavalry
Taczanka wz. 36
Szabla (sabre) wz.21 wz34
Pistolet maszynowy 9mm wz. 38 "Mors''
Karabin 7,92mm wz. 98 i wz. 98a "Mauser''
Lots of different types of Heavy guns and artilery
Tanks & ''Takiets'':
Czołg rozpoznawczy TK-3
Czołg rozpoznawczy TKS
Czołg lekki Vickers E
Czołg lekki 7TP
Czołg lekki Renault R-35
Czołg lekki Hotchkiss H-35
Czołg lekki Renault FT-17