As of now, there is no way to view yielded rewards in regards to swap fees without the use of an external dApp or tool. Some examples are, https://apy.vision/ & https://www.yieldwatch.net/. Some of these tools may also charge a subscription to view data on L2 chains.

A manual alternative would be to calculate daily fees rendered through the use of Sushi’s analytics. You can determine the % of daily fees you’ll receive by dividing the total value locked in the pool to the percentage of the pool your own.