This means that I need to spend a lot of time converting stuff over (though my artificer class is coming along nicely, and I think, will be great fun to play). Part of this has been adding a Veteran sub-race for the Warforged, and this is what I have come up with!
1) +1 Strength
2) A base AC of 16 - though you suffer Disadvantage on Stealth checks
3) Continue functioning when reduced to below 0 hit points. Whilst in this state, you suffer disadvantage on all attack rolls, skill checks and saving throws, and your speed is reduced by 50%. Enemies have advantage against you. You can continue to function in this state until you reach a negative sum equal to half your total hit points (so in the case of a warforged with 20 hit points, -10). At that state you shut down and become unconscious (though auto-stabilize due to your other racial benefits).
4) You unarmed attacks inflict 1d6 bludgeoning instead of 1d4