Unfortunately, that mod was not functional as the code added in the design template was incorrect. So I decided to recreate that Mod myself as I found the idea very interesting.
This Mod reduced all ship sized by 50%, makes them a lot smaller. This includes ALL your ship sizes and also including those of the AI.
However, the size of the weapon has also been reduced. Which was NOT done by me but was done by the original Mod author at Moddb found here
https://www.moddb.com/mods/distant-worl ... -scale-050

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I have not playtested this much so I don't really know if this effects Pirates as well. I don't think it does. So i till be updating this Mod to add pirates to the list.
Also, should I increase the shipscale of Capital ships and carriers to 0.75. For the entire size difference of destroyers and Capitalships to look more immersive?