I’ve been building up a library of FBX animations from a combination of MoCap stuff I’ve found around the internet and my own lovingly hand-crafted (though rather stilted – I’m not a natural animator!) clips.
I now have a folder of, for example, about 10 different walk cycles, but I’ve yet to find a good way of browsing those animations – a kind of video thumbnail preview integrated into Windows explorer would be ideal but, if that exists, I haven’t found it yet. In the meantime, one thing I have just found is this add-on that let’s you preview FBX animations in QuickTime player.
It’s a little clunky in places (including, for some reason, only allowing you to have a single FBX file loaded at a time, even after having started multiple instances of QuickTime player?) but it’s certainly made it easier to browse through my animation library than importing each clip into Blender as I was doing previously. Range of features and shortcuts shown in the screenshot below.