i think it should still be way easier then modyfing engine and modeling all weapons /armors in 3d
Nope, it wouldn't

. Actually even something as simple as a new hair style means a whole new model to develop. The number of pictures that needs to be drawn for this purpose = number of weapons * number of armors * number of actions that you can perform (shoot, walk, die, etc.) * number of directions (6) * number of frames per one animation (10 - 15) ... eventually it's something like 10k pictures to draw, only to make a new hair style. If only one person does it, it takes years to complete. With this system, adding anything new is nearly impossible. The game looks like a clone invasion and nothing can be done with it, unless 3d models are implemented.
As far as I know, Fonline engine already supports 3d, all is just the matter of making a model that is as close to the original as possible. Some people already work hard on that

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