Using MMD models with Desktop Mate

Start with permissions, not with Blender

This section is deliberately first, because it is the one that decides whether the rest is worth doing.

Official hololive models. Cover Corp has released official MMD models for its talents, and their use is governed by hololive production's derivative works guidelines. In broad terms those guidelines keep derivative works at a fan or hobby level, prohibit commercial use, and ask creators to avoid content the talents would find unpleasant or that presents them in a crude or offensive light. Converting a model to another format for personal desktop use is a derivative work, and the guidelines apply to it. Read the current text at the source rather than trusting a summary — including this one.

Fan-made MMD models. These carry a readme, usually in Japanese, with the author's own terms. Common restrictions include no redistribution, no format conversion, no modification, and no use outside MMD itself. “No conversion” is a genuinely frequent term, and it means exactly what this page describes is not permitted for that model.

The underlying character. Model permissions and character rights are separate. A fan-made model of a game character can be freely licensed by the modeller while the character remains the property of a publisher.

If any of the three is unclear, the honest answer is to pick a different model. There are plenty.

Why conversion is necessary at all

MMD models are .pmx files built around MikuMikuDance's own conventions: a Japanese-named bone hierarchy, a morph system for expressions, MMD-specific material flags, and a rigid-body physics setup for hair and clothing.

VRM standardises all of those differently. It defines a fixed humanoid bone list so any application can animate any model, uses its own expression definitions, uses MToon materials, and uses spring bones for secondary motion.

So a conversion is not a file-format change. It is a re-rig, a re-material, and a re-physics job, with an export at the end. Tools automate parts of it; none of them automate all of it well.

The conversion workflow

The current route runs through Blender with the VRM Add-on for Blender.

1. Install Blender and the VRM add-on. Match the add-on release to your Blender version — this is the step that breaks most often, because Blender 4.x releases have repeatedly broken older MMD-side add-ons.
2. Import the PMX. An MMD import add-on handles this. Expect the import itself to be the easy part.
3. Map the armature to VRM humanoid bones. This is the core of the job. VRM requires a specific set of named humanoid bones, and MMD's Japanese-named hierarchy does not line up with them. A missing required bone blocks export outright; a mis-mapped one produces a model that exports cleanly and then animates wrongly.
4. Rebuild expressions. MMD morphs do not map onto VRM expression definitions automatically. Blink and basic mouth shapes are worth the effort; the long tail of MMD morphs usually is not.
5. Convert materials to MToon. MMD material settings do not survive. Models that skip this step are the ones that import "successfully" and then render invisible or flat white.
6. Rebuild spring bones. MMD rigid-body physics for hair and skirts has to be redone as VRM spring bones. Simplify aggressively; a desktop mascot does not need concert-grade hair simulation, and every bone costs frame time on your actual desktop.
7. Set licence metadata and export VRM 1.0. Fill in the author and permission fields honestly — if the source model's terms restrict use, that restriction belongs in the file.

Newer workflows push the MMD-side preparation into external tools and keep only the VRM add-on on the Blender side, which sidesteps the add-on breakage that comes with each Blender release. If you are starting fresh in 2026, check what the VRM add-on's current documentation recommends before committing to an older tutorial.

Loading the converted model

Once you have a VRM 1.0 file, the loading procedure is identical to any other custom model, and carries the same caveat: Desktop Mate has no publisher-supported way to load one. The community Custom Avatar Loader is the usual route, its repository has been archived since 4 December 2025, and it targets MelonLoader 0.6.6 with .NET Desktop Runtime 6.

Work through the safe install checklist checklist, and keep Steam > Desktop Mate > Properties > Installed Files > Verify integrity as the recovery path. Details specific to the loader are on the Custom Avatar Loader page.

What a converted model looks like in practice

Set expectations before you spend an evening on this. A converted MMD model in Desktop Mate will generally be heavier than a purpose-built VRM, because MMD models are made for a renderer that only has to draw one character at a time and not for something sitting on your desktop all day. Expression range will be narrower than in MMD, because only the expressions you rebuilt survive. Hair and clothing will move differently, because the physics system is not the same one. And detailed models may read as noisy at desktop-mascot scale, where the character is a couple of hundred pixels tall.

None of that makes the conversion pointless. It does mean that a simpler source model usually produces a better result than an elaborate one, which is the opposite of most people's instinct when browsing.

Using MMD models with Desktop Mate FAQ

Sources and verification

• hololive production derivative works guidelines ↗
• hololive official MMD model release page ↗
• VRM Add-on for Blender ↗
• Blender download ↗
• VRM format specification and documentation ↗
• Custom Avatar Loader repository (archived 4 December 2025) ↗

Checked against the sources above on 2026-09-01. Desktop Mate, its DLC line-up, and community tooling all change; recheck the originals before acting on anything time-sensitive here.