Japan never actually trialed the F-16 for this competition. The F-16J was initially offered as a basic model to early F-16A standards, but they failed to have a demonstrator aircraft ready to be flown and only had Japanese pilots observe it from an F-4 flying alongside it.
It also didn’t meet the minimum requirements of the competition, namely the 4 + 4 IR/SARH missile air superiority loadout unlike the F-14J and F-15J proposals, so it was rejected (initial F-16J had no SARH missiles at all). The F-16AJ in game is based on the follow up proposal, which was based on earlier AIM-7 Sparrow testing on the YF-16, something the US discarded because there was no need for it at the time. This included capabilities for up to four SARH missiles with two mounted wo launch rails attached to the landing gear.
This would’ve been enough to meet the minimum requirements, and would’ve offered more versatile air to surface armament with TV guided missiles and bombs advertised in the brochure that the F-16 could already use. But it was too late to make a difference and the F-15J was selected instead.
In game it’s not entirely this though, because Gaijin decided to remove half of the SARH missiles for a more conventional design similar to the F-16 ADF (built to entirely different requirements over a decade later), removed TV guided bombs despite them being on other early F-16s in game and gave it the ADF’s engine that also didn’t exist yet when the F-16J was proposed or would’ve entered service. They also ignored all visual differences between the F-16J and the Block 10 model that the in-game F-16AJ uses.
The camo is also based on the F-15J instead of real F-16J promotional material, so it’s the only aircraft I know of that only has camos from entirely different aircraft types (F-15J, XF-2A, F-2A)