You could do try to do this with an automation? The idea is that you can only apply rich text formatting to a field via an automation, and so let's say your rich text field called "Notes" currently has the text "Project Name". You would have to create an automation that would update that field to be "# Project Name", like so:
And this would make all the values in that field be bold
This gets complicated if your cell value is like the following though:
```
Project Name
Project Details
Project Details
```
But potentially still solvable assuming there's a pattern that we can identify the project name values