Is there tether support for canon 70D in Lightroom 6
It isn't on the list of supported cameras, but I don't know if that list has been updated. According to what is published, there is no tethered support for your camera.
Tethered camera support in Lightroom
Unfortunately not: Tethered camera support in Lightroom
It is there and working as of Lightroom 6 https://helpx.adobe.com/lightroom/kb/tethered-camera-support-lightroom-4.html
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