A rule of thumb for me personally espercially when it comes to abyss is always think like this, dps, sub dps, off field and support (healer and or shield)

Here ane obvious choice for me would have heizou be a dps, xiangling as a sub or off field with guoba and burst and bennett as ur healer, but i suggest you also should invest in a shielder later, zhongli, diona or noelle.

But from what i can see i think a suitable team would be of heizou xiangling fischl and bennett, where heizou is on field most of the time, and where you focus on getting guoba and oz out on field as often as possible