Available as an assembled Module and as a DIY project.
This Module is currently available.
Converts Stereo Euro to Stereo Line and Back Again
The AI026 Eurorack Line Interface converts between +/- 2V Line Signals and +/- 5V Eurorack signals. This allows for the best headroom and highest quality when processing Line signals with Eurorack modules, and vice versa.
https://aisynthesis.com/product/ai026-eurorack-line-interface/
These merchants probably sell this module. Huh?
AI Synthesis AI026 Line Interface
AI Synthesis AI026 Line Interface