Can I bulk edit certain variants under a product?

You can certainly edit several variants under a product in batch via EasyBy. 

1. Create a bulk edit task, and select "Product must match specific products" in step 1.
2. Click "Add products" on the page.
3. Select the variants you'd like to edit.
4. Set up the rules how you want to edit those variants in step 2
5. Preview the edit result in step 3
6. Click "Start edit now" or "Schedule edit" in your preferred  time.

Congratulations! You're all done through the above steps!