Hi there, simeondhuman.
Please correct me if I'm wrong, do you mean adding a bunch of transaction in the sub-account? If so, we can add multiple transactions to it. Let me walk you through on how to do it:
To add more transactions into this sub-account, click the Add drop-down arrow below the Date column. Still the same with the process, enter any information needed before saving it.
Know that if you still need help, I'll be here to help you. Just let me know by adding a new post below. I hope you're doing good. Take care!
Are these transactions that you've already entered?
In Category = Main Category but want to move as a batch to Category = Sub-Category?
Short answer - No, I don't think so. You'll have to do them one at a time.
If these are the only transactions in that Main Category, you could make that Main Category into a Sub-Category but I don't think there's a way to Batch Reclassify.