I-864 Petitioning sponsor vs Joint sponsor required documents

[Msafiri]

So, the petitioning has to file form I-864 even if their income doesn't meet the requirements, and you have a joint sponsor...right?
Does the petitioning sponsor have to submit W-2 and tax transcripts even if the joint sponsor submits those documents?
In other words, do you have to submit 2 sets of accompanying documents (W-2s, transcripts etc) for both the PS and JS?

Tyia.

[newacct]

yes

[Msafiri]

Thank you.