what type of shears they were using
In the Comments to the first video (both shown as posted by Leons Choice) 'Leon' mentions: these tools I made by myself.
Here are some other tools used by Leon: https://www.youtube.com/watch?v=QP6sBLcYeXQ.
A lot less persnickety but rather cruder tool can be made from very heavy gauge wire bent into a tight U
shape (with spiraling of the blunt end if necessary to add springiness) and the sharp ends bent at right angles but parallel to one another. Something vaguely like the top pair of needle-nose pliers here but with a spring in the handle so the points open when the tool is not squeezed.
For the large scale there are alternatives :) https://www.youtube.com/watch?v=Spgc-REEUa4