Good evening Carly and welcome back!
Thank you for reaching out to us.
I would love to help you with this topic.
Is there a way to do a bulk action addition of a saved fieldset without going into each individual event?
Alas, there is no built-in solution to allow bulk update of that nature for the time being.
That being said, although it is unsupported, you could definitely consider to get an SQL query together for that purpose.
If coding is not really your cup of tea, you could always hire one of our recommended customizers to do the customization for you.
I wish I had a better answer for you, but for now it’s the best one I have unfortunately.
Best regards,
Geoff B.