A model for this version actually exists, meaning even in the early days, Wargaming was at least considering ways to add smoothbore guns to the game.
There will be many more unusual configurations in the archives, but I think nothing even comes close to this one.
The SU-152 model includes both KV-7 armament configurations as selectable gun models.

This technically makes it:
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The second truly double-barreled vehicle in the game (after the MTLS)
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And also the first triple-barreled tank ever modeled in the game

Source: T-62A 115 mm, SU-152 KV-7 config


WG: SU-152 with 2 and 3 gun configurations, nah, that’s too much.
Lesta: Of course, why not?
It is only a matter of time.