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Google translation: "I am trying to apply the auto correction feature of LR to a large number of photos at a time. I'm not talking about duplicating or applying a specific correction to a set of photos, but using automatic correction to a large number of photos before making a hard copy. How to do ? I do not find... Thank you !"
In Library Grid view, select the desired photos. Then in the Quick Develop panel on the right, click the Saved Presets menu and select the preset Classic - General > Auto Settings:
If you don't see the preset group Classic - General, it's currently hidden. Go to the Presets panel in Develop, right-click the group User Presets, and do Reset Hidden Presets:
While you could also use Auto Sync in Develop, I highly recommend against it -- many people forget to turn off Auto Sync afterward and end up changing many photos by accident and discovering it too late.