I have been doing a bunch of splicing of single-braid Dyneema (AmSteel) lately—lots of storm preparation.
The stuff is seriously difficult to cut without making a mess of it, particularly when cutting single strands to taper the bury, but these scissors from D-Splicer do a lovely neat job and will even cut through a full 12mm with a single easy snip, even though mine are only meant to go to 10mm.
I have had a couple pairs of scissors that purport to be for Dyneema before, but these are way better. Highly recommended and worth every penny of their admittedly eye-watering price.
For ease of cutting Dyneema while making soft shackles, I found the ceramic knives by CeramicKnife.org Ontario CA to be handy. The Riggers folder or the EOD knife are my go to blade when triming dyneema strands for tapering or cutting line to length.
I also found that the ceramic knife stays sharper longer. I have had both the D-Splicer scissors and their ceramic knife. Think the scissors was great to start with but was less effective over time.. Knife is still going well