As of Windows 10 Insider build #17643, you can copy/paste text from/to Linux/WSL Consoles!!!
We know that this is a feature MANY of you have been waiting for - our sincerest thanks for your patience & continued support while we untangled the Console's internals, allowing us to implement this feature.
To ensure that we don't break any existing behaviors, you'll need to enable the "Use Ctrl+Shift+C/V as Copy/Paste" option in the Console "Options" properties page:
With the new copy & paste option selected, you'll be able to copy and paste text using [CTRL] + [SHIFT] + [C|V] respectively.
Note: This setting can be set independently for each shell or shortcut: If you pin your shortcuts to your favorite shells (e.g. Cmd/PowerShell/Linux) to your task bar, and modify the properties of Consoles launched via these shortcuts, your settings will only be made to the affected shortcuts. If you later launch the same shell via the Start menu, or the run dialog, your settings will not be found as they'll have been saved to your pinned shortcuts, not your Start menu tiles/shortcuts, or registry settings.
Please let us know how you get on with this feature If you find any issues, please lookup/post issues on our GitHub issues repo. If you have other feature asks, please find & upvote, or post them on our UserVoice