Here is a Project description column example that displays the first 100 characters. If you want the project name, just change {description} to {name}
valueexpression=CONCAT(LEFT({project}.{description},100),"...") valueformat=HTML
displayname=Project Description
The CONCAT is just there to add "..." to the end of the description, that way a user knows that there may be more text that they're just not seeing in the report. You can omit the CONCAT() portion if you choose, so it would just be:
valueexpression=LEFT({description},100).
If you want to get REALLY fancy and only add the "..." when the description is > 100 characters, you'd use this:
valueexpression=IF(LEN({project}.{description})>100,CONCAT(LEFT({project}. {description},100),"..."),LEFT({project}.{description},100))
valueformat=HTML
displayname=Project Description
That being said, I think what you really want is to REMOVE a specific number of characters from the end. I don't know of a straight forward way of doing that. This page may help you though: https://one.workfront.com/s/document-item?bundleId=the-new-workfront-experience&topicId=Content%2FRe...