From Valve Developer Community

Scene configuration

The Blender Source Tools allow Blender to import and export Studiomdl Data and DMX model files.

Features

One-click export and import

SMD and DMX

FBX enjoys limited support in studiomdl shipped with CS:GO update 1.34.8.4

Support for most Blender features

Export multiple objects to one file

Compile QCs automatically

Import complicated models by QC

Installation

Install Blender 2.80 or later. Or Install from Steam (AppID: 365670) Download the Source Tools. Don’t unzip. In Blender: Select Edit > Preferences Move to the Add-ons tab Click Install... at the top-right of the window Find the downloaded zip file and select it (Double click) 'Blender Source Tools' should be the only add-on shown if installed correctly. Check the box to the left and wait a moment for activation to complete.

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