Go to File > Load Motion Data and select your K-pop VMD file.
Finding high-quality motion data requires knowing where the "motion makers" hang out. The community is spread across several major platforms: Kpop Mmd Motion Dl
The primary hosting site for Japanese and international MMD creators. You will often need a link from a video description to find the specific file here. Go to File > Load Motion Data and select your K-pop VMD file