This is the party version of my Bursting Revamp Shadowlands/pre-patch weakaura here:
Focus version:
This version automatically attaches to party/focus frames and gives a rough idea if bursting alone will kill a player.
Firstly, it cannot grab another players versatility so you may slightly survive better than it anticipates.
Secondly, I did not apply any damage reductions to the calculation since it risks becoming too overcomplicated with that.
You can change if you want the text to show or not under custom options.
On the third screenshot you can change the side of the frame you wish them to attach to by selectiond the 2 yellow sections:
Weakaura and Group Tab
Change the marked red selectors to be the side you want them to attach to and change the blue selector to the opposite option.