Hello, milonedp.

We were unable to add a client to the line item at this moment. I understand how the workflow you seek will benefit your company.  

We can submit a request for this feature through our Feedback board. These requests and suggestions are forwarded to the Product Development Team. They'll review them and may consider your input for future updates. 

Here's how: 

1. Access your QuickBooks Online company.
2. In the upper-right corner, click the Gear icon.
3. Under the Profile column, select Feedback.
4. Enter a brief description of your product suggestion, and then click Next.
5. Type your email address.
6. Once done, click Send Message. 

You'll want to track your suggestion through this website. You can also visit our blog to keep up with all of our recent events and developments.

I appreciate your patience as we work through this. If there's anything else I can do for you, please let me know. I'll be around to help you out. Stay safe!