While many direct links on Microsoft's site have been retired, you can still find these packages through several reliable channels:

Many other languages like Bulgarian, Croatian, Czech, Danish, Dutch, Estonian, Finnish, Greek, Hebrew, Hungarian, Korean, Polish, and Turkish are also available. Installation Guide

Developers can use the WEDU 1.2 tool to automatically scan for and download available updates and language packs for their distribution shares.

Installing a language pack in WES7 involves a specific sequence of steps through the Control Panel. Windows® Embedded Standard 7 SP1 Language Pack

Some MUI packs, like the Multilingual User Interface Pack 1 for WES7 SP1 , were historically available for 32-bit and 64-bit systems.

Arabic, Brazilian Portuguese, Chinese (Simplified/Traditional), French, German, Italian, Japanese, Russian, and Spanish.