I have figured out a few more things about how to convert CMU bvh files to vmd.

1. The "hip-uncorrected" bvh files are more MMD-compatible than the "hip-corrected" bvh files. "Hip-corrected" means that the resting pose (Blender edit-mode pose) of the hip bone will be located at the world origin(0,0,0). These BVH files have been "corrected" to make them compatible with DAZ characters whose rest pose hip bone location is at the world origin(0,0,0). MMD models do not have their center bone located at the world origin, however, so the "hip-uncorrected" BVH files are more compatible with MMD models.

2. The CMU bvh files have a frame rate of 120 FPS (120 frames per second). VMD animations normally have a frame rate of 30 FPS.
To correct the frame rate, you need to manually set the frame rate of your Blender scene to 30 FPS. When you import the BVH file, you need to enable the Scale FPS option to change the frame rate from 120 FPS to 30 FPS.

3. In the CMU BVH animations, the character's rest pose (edit mode pose) is a T pose with the arms outstretched at a 90 degree angle from the body. MMD models have the arms rotated downward at a 45 degree angle in an A pose (or collar bones rotated down 5 degrees and shoulder bones rotated down 40 degrees). To convert the animation from being T-pose-compatible to being A-pose-compatible, before you export the BVH animation to VMD, go to the first frame of the animation and rotate the character's left arm 45 degrees, and rotate the character's right arm -45 degrees. When you export the animation to VMD, enable this export option: "Treat Current Pose as Rest Pose".

The Blender bvh importer has a bug. If you try to import a bvh file which has Japanese bone names, it won't import into Blender, and you get an error message. This simple fix worked for me:

Open this file (from the Blender program folder) in a text editor, such as Notepad++:
scripts\addons\io_anim_bvh\import_bvh.py

Change line 97 from:
    file = open(file_path, 'rU')

to:
    file = open(file_path, 'rU', encoding = 'utf-8')

I am also figuring out how to convert BHV to VMD.  There are a lots of BHV files but I can't use in MMD
VMD to BVH is Oke, opposite is not

Thanks for your test.

Okay, if you read my comments below, you can see that I have been making some progress in figuring out how to do BVH to VMD conversion, but once again this effort has hit a snag. In MMD, the character's arms are bending behind her back when they should be bending forward in front of her.

Another problem. With the "hip-corrected" bvh files, the hip is located at the world origin(0,0,0) in Blender edit mode. Because of that, the character will be floating about a meter off the ground when the .vmd file is imported into MikuMikuDance.

Another problem that I have found to convert the CMU .bvh files to .vmd files:

The scaling of the imported skeleton is roughly 10 times too big for MMD, which means that the animation of the character's location needs to be corrected for each and every keyframe.

It looks like this problem is tough nut to crack.

There are a few problems with converting these bvh files to vmd files:
1. The need to rename bones to Japanese bone names.
2. The bones in these bvh files do not have any equivalent for MMD lower body bone, no equivalent for MMD mother bone/root bone, no equivalent for MMD leg and foot IK bones.

MikuMikuMoving does import/export of bvh and vmd.
Blender with the MMD tools add-on by powroupi can do import/export of both bvh and vmd.

I don't think that you can find any bvh files which have the MMD standard Japanese bone names though. Renaming of bones is needed. So there isn't a perfect solution yet, but I'm sure it is only a matter of time.

There is a Blender add-on which (I think) is called Motion Capture Tools, which can be configured to re-target an imported bvh animation to a skeleton which has different bone names.