When Did The Roman Army Standardize Using Plate Armor?

[CaesarAugustus]

https://www.europabarbarorum.com/faction...units.html

This game mod is realistic and has unit descriptions, I heard scholars offered advice for the game. 

I suspect it only has Roman units from the early Marian reforms, possibly 107 BC-40 BC. I'm guessing after 40 BC, plate armor became more common.

If I remember correctly, the first plate armor has been found in the probable field of the Battle of the Teutoburg Forest (9AD).
But at the time probably it was not a common armor.

After, we can see it as standard armor in all main representations in the period of hereditary emperors, and also later (under Caracalla, for example). It was (almost) probably abandoned after the creation of the centralized armories.
Sometime you may hear an opposition concerning the Tropaeum Traiani in Adamclisi, which panels are supposed to describe Dacia conquest, where the plate armor is not shown (I think something similar to the plate armor is just in the panel that is now in the Istanbul Museum). But, it is just a theory that the panels are representing Dacia conquest done under Trajan. The Tropaeum is a recent reconstruction, and Panels style is far from being associable with the classical style of the time, and that panels have been associated to a later period, even to middle ages. Not to consider that the panel order has been sorted just to resemble the a priori reconstruction... in short, not a significative opposition.