That looks like a fantastic squad for Sumire, congrats! I have thought long and hard about putting a shield inherit on my Sumire team and ultimately decided that a board changer would be dual purpose (board refresh and emergency supply of hearts for a heart-cross) and therefore more useful than a straight up shield inherit. I was browsing your Padherder and noticed that you have a couple of Ronia's sitting in your box. I know that Urd is incredibly valuable for your Shiva team (she was an MVP sub for mine as well before I moved on to other leads), but I think that you'll get more value out of her active on a team that can progress you deep into end game. Just some food for thought, you could inherit Urd's AS onto Paulina, and inherit Ronia's board change onto a member of your Shiva team - freeing up Urd's sweet AS for your Sumire team. A burst active could be useful on a Sumire team, but fitting it onto the team can be a bit cumbersome. Something like A. Sun Quan's AS is best left as an inherit on the team IMO. The extra damage is always welcome, I can't say with certainty that it is needed at this particular time in the game (unless you don't have teams that have stratospheric damage output already - Sumire is very much a tank and spank team.) As for where to place such an AS, I'd probably not put it on a Sumire, because the haste system is what defines this team's playstyle. It'll be on either of your flex slots most likely. Personally, I would wait to see how things go in the next little bit before I went and inherited skills onto my entire team. For now, if I were you, I'd stick with a board change that makes hearts on Paulina and a delay on A. Isis. Using that as a solid base to start from, you can then decide if/what tweaks are necessary.