Switch your graphics options to Advanced, then turn down lighting quality so it isn't max. The second-highest setting is exactly the same, but without engine trails.
As for the Borg engines, you'll need to right-click and Disable Visuals. No way around that.
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The only way I was aware of how to remove trails was via ... unofficial means.
As for the Borg engines, you'll need to right-click and Disable Visuals. No way around that.