You are overthinking it, anticipating rather than actually having a problem.
And here’s the kicker: what if the phono module you choose doesn’t sound great? They make a much larger audible difference than phono cable length.
I have 3 different length phono cables, to a SUT with it’s factory attached phono cable.
the longest 8lf din/rca one for my far left tonearm custom made for me by Pine Tree.
discuss your needs, pick your length and connectors, they will make it very promptly.
main arm, 1m ortofon, oh boy
the 3rd phono cable came with my Acos Lustre GST-801 tonearm, possible OEM or seller got it.
Despite all the BS about ’keep phono cables short’, I nor anyone else can hear the difference between any of them when I move them hither and thither.
I relocated my SUT, could shorten the 8lf one, I’m not gonna bother.
IF you go into a SUT (with PASS for MM), to a Phono Stage, then to a Preamp, then to an Amp you have 4 lengths of cables involved. It’s the phono stage that is going to determine the sound, not the cable length of any or all of them.
One of the reasons I do not like ports in speakers is so that I can put equipment between the speakers with no side or rear radiation.
have a peek at my turntable between my speakers
the isolation feet below my TT Plinth is to tame my springy wood floor’s flex, not any sound waves in that location, just enough to get 2 steps away after needle drop..