I doubt you will notice a difference, but why would you do that? Does that mean that you will have to buy a 2 meter pair AND a 3 meter pair of the same speaker cables, then only use half of each pair? It makes no sense to me, but to answer your question, no, you shouldn't hear a difference.
Mono amps and different length speaker cables
Wondering if there is any noticeable negative effect from using say a 3 meter pair of speaker cables to one set of binding posts on the amp and speaker and using a 2 meter pair of the same brand and model of cable to different binding posts on the amp and speaker. I am using solid state mono amps.