If you're referring to your Receive Payment screen, Outstanding Transactions are automatically sorted by date in the DESCRIPTION column.
In the event you're inquiring about being able to sort them by their memos, currently there isn't an option for that. I can see how this could be a useful feature for yourself/others and have submitted feedback to our developers about it.
You can also send your own feature requests while signed in.
Use your Gear (⚙️) icon.
Enter your suggestions and/or comments.
Choose Skip and send message.
The available drop-down menu can be used to pick an appropriate category.
Select Send message.
Your feedback's definitely valuable to Intuit. It goes to our Product Development Team for review and will be considered in future updates. Feature requests can be tracked through the Customer Feedback website.
I'll be here to help if there's any additional questions. Have a great day!