Seeing how Capcom attacked the 4:3 to 16:9 issue for the Resident Evil Remake-Remastered version, it made me think of perhaps a possible solution for the old school RE games (Zero, Remake, 2 and 3) for proper 16:9 support.
Perhaps we could stretch the 4:3 image to a 16:12 image to keep the ratio as the original (4:3 x 4 = 16:12).
That's one option.
I don't know if the TV will simply not take the other 3 height units into consideration or not, if the TV DOES NOT take them into consideration, then we might have a proper 16:9 image of the game by keeping the backgrounds like they are as well as the 3D models intact and without any misplacement.
Although, at the cost of 1.5 height units at the bottom and upper parts of the whole 4:3 image, but I don't think that would be bothersome at all. If the TV does take the whole image into consideration, then another optiono could be to remove 1.5 from the top and bottom parts of the video output leaving it as a 16:9.
I am just talking about purely theoretical stuff, I don't even know if it could be implemented or not as a cheat code or any other way to do it.
Something like this:
4:3
16:9 (Top and bottom portions of the original 4:3 image cropped)
And just for better reference, the menu would look like this: