Hi, BillyBon. 

I can see how being able to batch add a category to multiple transactions is beneficial to your business. As mentioned by my colleague above this feature isn't available in QuckBooks Online. 

Please know that we roll out updates based on our customer's request. Rest assured, we're taking note of your ideas and suggestions to improve your QuickBooks experience. 

In the meantime, I suggest visiting the Firm of the Future website to stay updated with new features and options. It also contains product news about any changes.

If you have any follow-ups or other concerns, please leave a comment below. I'm here to help. Have a great day.