Question about new one handed attack animation

[Tuidjy]

I just downloaded the mod, and I noticed that some enemies use
a one-handed attack that I do not recognize.  They hold their sword 
behind their head, and strike from above and from the right. I tried
to reproduce it, and even succeeded once or twice, but I cannot
figure out how I did it.  It seems that it's a variation of the
'horizontal slash from the right'.

Can someone give the specifics of this attack? Is it just for flavour,
or is it different in damage, speed, blocking requirements, etc?
Are there other new attacks in this mod?  Thanks.

 

[Almalexia]

Its just for added flavor.