Thanks, Speccy team! Most of the strings are now translatable/have been translated. What is missing:
"Not supported" (in Hyperthreading - CPU sector)
"Level x" (in Current Performance Level - Graphics sector)
"Find" (title bar of Find dialog)
"No network shares" (in Network Shares - Network)
"Version", "Vendor", "Renderer", "GLU Version" (in OpenGL - Graphics)
"Uptime Statistics" (Uptime - Operating System)