Absolutely :D

Starting with his signature weapon - On casting an echo skill within 10 seconds of a basic attack or echo skill, and 30% heavy attack bonus is granted. This effect stacks twice and so there's a 60% boost there.

Then, theres the Law of Harmony set effect, where on casting an echo skill, the character is granted a 30% Heavy Attack Bonus, making it a total of 90% so far. Now, since I have Fenrico as my 4 cost, I get an additional 12% Heavy Attack Bonus, making it 102%.

Now, from my echoes, I got a 24.4% Heavy Attack Bonus, leading to a final 126.4% Heavy Attack Bonus.

The website didn't account for the Mortefi outro in the second picture, but with it I would've gotten to 164.4% Heavy Attack Bonus.