I had a quick look at the in-game Global Directory, and this should be all of them (hopefully).
I also included the upcoming AS21 Redback as it was tested by some players earlier.
AT = AT Squad, MO = Mortar Squad, SN = Sniper
Vehicle Tier AT MO SN
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PL-01 10 ✓
Merkava 4M 10 ✓
Kornet-D1 10 ✓
T-15 Armata 10 ✓ ✓ ✓
AS21 9 ✓ ✓ ✓
Hunter AFV 9 ✓ ✓ ✓
Merkava 4 9 ✓
Kurganets 9 ✓ ✓ ✓
Griffin 50mm 8 ✓ ✓ ✓
K21 8 ✓ ✓ ✓
M2A3 Bradley 8 ✓ ✓ ✓
Marder 2 8 ✓ ✓ ✓
Rosomak M1M 8 ✓ ✓ ✓
Dragun 125 8 ✓ ✓ ✓
CV90 Mk.IV 8 ✓ ✓ ✓
BMD-2M 7 ✓ ✓ ✓
BMP-3M 7 ✓ ✓ ✓
BWP-2000 7 ✓ ✓ ✓
Rosomak 7 ✓ ✓ ✓
Type 89 IFV 7 ✓ ✓ ✓
Warrior 7 ✓ ✓ ✓
BMD-4 6 ✓ ✓ ✓
BMP-3 6 ✓ ✓ ✓
BVP-M2 6 ✓ ✓ ✓
ZBL-08 6 ✓ ✓ ✓
C13 TUA 6 ✓ ✓ ✓
BMD-2 5 ✓ ✓ ✓
BMP-2 5 ✓ ✓ ✓
OT-64 5 ✓ ✓ ✓
BMD-1P 4 ✓ ✓ ✓
BMP-1P 4 ✓ ✓ ✓
BWP-1M 4 ✓ ✓ ✓
ZBD-86 4 ✓ ✓ ✓
BMD-1 3 ✓ ✓ ✓
BMP-1 3 ✓ ✓ ✓
M113 ACAV 3 ✓ ✓ ✓