You can find this on Natural Stat Trick.
Search Ty Emberson Natural Stat Trick.
In the tabs set the years you are interested in then choose
5 vs 5 : One Ice : Counts: Opposition
Or you can use the "line tool" to see how he did against individual teams or individual players. For example vs Toronto and the specifically vs Mathews:
Note: Line Tool requires you to list two players on the original team. If you want to only see one guy you have to list his name twice.
In the later link it looks like he was on the ice for roughly half of Mathews shifts.
Hockey Reference has a pretty good splits section:
Scoring Stat Splits for Ty Emberson for 2023-24
www.hockey-reference.com
It is year by year. One advantage of Natural Stat Trick is that you can for free get cumulative data for a three year period. I like this because I have always tended to use three years as my generic averaging time frame.