I am trying to export animated character from Blender to THREE.js JSON using official THREE.js blender exporter. I have tried a few models from the internet and also a model included in THREE.js: https://github.com/mrdoob/three.js/blob/dev/examples/models/skinned/marine/marine_anims_core.blend
Exported JSONs are tested in this example: https://github.com/mrdoob/three.js/blob/dev/examples/webgl_animation_skinning_blending.html
Imported models are animating badly + model has a wrong x rotation (-90deg). The rotation can be repaired by rotating imported object in THREE.js. However it rotates the bones too and so not fix the problem. I think the problem is bad rotation of skeleton in relation to the model.
Blender: 2.73, 2.79, THREE.js: r77, r88, Chrome
Example: Wrong animation video