The animation_lengths for the GH of the mercs are as follows

6 Rogue
8 Townguard
9 Iron Wolf
5 BarbMerc-1hs
5 BarbMerc-2hs (not in use as of v1.09, but it appears that there are some wandering about in some of the v1.10 screenshot previews)

None of the mercs have any blocking animations, this include the Iron Wolves.