Well that's not correct at all.
The Brewster Buffaloes were sold by USA to Finland during Winter War. They weren't "German captured".
Finland flew a hodgepodge of different planes. During Winter War we had the following types:
Bristol Blenheim Mk.I
Bristol Blenheim Mk.IV
Fokker C.X
Brewster B-239
Bristol Bulldog IIA
Bristol Bulldog IVA
Fokker D.XXI
Fiat G.50
Gloster Gladiator
Hawker Hart
Morane-Saulnier M.S.406
Those types above were used in combat. The types below were used for training, scouting and recon, mail&communication flights and for transportation:
Aero A-32 GR
Avro 652A Anson I
Blackburn Ripon IIF
Cessna C-37
De Havilland D.H.60 & 60X Moth
Douglas DC-2
Fairchild 24J 60 De Luxe
Fieseler Storch Fi 156 K-1
Jaktfalken II
Junkers F 13
Junkers A 50 Junior
Junkers W 34 & K 43F
Koolhoven F.K.52
Letov S 218 A Smolik
Raab-Katzenstein RK-26 Tigerschwalbe
VL E.30 Kotka I & II
VL Pyry
VL Sääski I & II
VL Tuisku I & II
VL Viima I & II
The VL planes are Finnish domestic builds - VL is short for Valtion Lentokonetehdas, literally meaning State Airplane factory.
Then, we got a bunch of planes as loot from Soviets:
Iljušin DB-3M
Polikarpov I-15
Polikarpov I-16
Polikarpov I-153
Tupolev SB-2
The bombers were used as such, while the fighters were too ****ty, so they were only used to familiarize pilots with enemy equipment and for target practice and so on.
During Winter War, the FAF was organized into seven regiments. Four of them (1, 2, 4, 19) were combat regiments while the other three were training units. 19 was not full-sized and consisted entirely of Swedish volunteers.
By Continuation War, the equipment was being standardized as much as possible. As the war went on, Finland could buy some planes from Germany. Thus, we used the following types during that period:
Brewster B-239
Caudron-Renault C.R. 714
Curtiss Hawk H-75 A-2
Gloster Gauntlet II
Hawker Hurricane I
Messerschmitt Bf 109 G-2/6/8
VL Humu
VL Myrsky
VL Pyörremyrsky
Dornier Do 17 Z
Junkers Ju 88 A-4
Høver M.F. 11
SB-2
Again, the three VL's were domestic prototypes, only built in very small numbers.
Organization was changed. Regiments 1, 2 and 3 had only scout and fighter planes, while regiment 4 had bombers. Regiment 5 was responsible for Åland and the coastal sea zones and operated with captured Soviet equipment.
The Finnish flying aces were only second to Germans. Ilmari Juutilainen had 94 kills, making him the best non-German ace ever. Hans Wind had 75 kills, Eino Luukkanen had 56, Urho Lehtivaara and Oiva Tuominen both had 44.
The uniform was very similar to the army uniform, though pale blue in colour. The swastika in the FAF flag comes from Swedish heraldry, not Nazi. The first plane of FAF was donated in 1918 by a Swedish count Eric von Rosen, who also flew it to Finland and participated in the War of Independence, so his family herald was adopted into the FAF flag as well: