The Cost Rate module allows you to set up a cost code and cost rate by Project for timesheets. The rates could be set with different cost codes depending on the sequence you want the system to retrieve the cost rate.
NOTE: Employee cost rate is already available in the employee setup, but in some cases you might have a different cost rates by activity/WBS and in that case you would use Cost Rate setup by WBS.
For example if you have the following rates:
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