Hey there, it's definitely possible to edit variations (including option-based prices, quantities, and/or SKUs) for as many listings as you like. However, when using bulk edit the updates you perform will replace the existing variations for all the listings you select, so you need to recreate everything. As shown in the video, the first step is to choose your category(s). This is necessary because the category(s) you select will impact the properties, options, and scales that are prompted.
Alternatively, if you wish to update variations for a single listing you can do so by updating that listing directly without having to re-create everything.
Examples of how to do both are covered in the video, but please let me know if you have any questions or if you'd like to connect and walk through things together.
http://help.getvela.com/using-vela/how-to-videos/variations
