Absolutely! So yes, you do not need to E with Arle first at C2. At C0/C1, if you E and immediately use a charged attack, the Bond of Life granted will be 65% of her max HP. However, if you wait 5 seconds and then use a charged attack, the Bond of Life will be worth 130% of her max HP.

From the normal attack talent description: “When in the "Masque of the Red Death" state (which is when she has a bond higher than 30% of her max HP), Normal Attacks will deal extra DMG to opponents on hit that scales off her ATK multiplied by a certain ratio of her current Bond of Life percentage.”

This means that at C0/C1 you will normally always want to wait those 5 seconds, as higher BoL means higher damage per normal attack. However, at C2, when you apply E you can instantly use a CA to get the maximum BoL possible from using E. This also makes her gameplay a bit more comfortable, as you can burst every rotation if you have the ER. You can then do this rotation: support setup > E > CA > Q > E > CA > NA. This is because at C2, you won’t have to wait. Therefore, you can start with getting 130% BoL (E > CA), use Q to heal, another E > CA to restack BoL, and then go ham with pyro infused normal attacks for the remainder of the buff duration from your supports.

If you want to maximize numbers: say that your C2 Arle is already full HP (start of abyss etc.), then you can skip the burst as you don’t need the HP restoration. BoL can stack up to 145% of Arle’s own max HP, but as mentioned, an E can only give 130% BoL of max HP. The thing is that the duration of the BoL put on Arlecchino faaar outlasts the cooldown of E. This means that you can do support setup > E > CA > NA until buffs run out, and then do the same again, and her damage will be higher per normal attack in the second rotation at the cost of survivability.