If your question is whether SEP-2 and the constitution proposal are separate proposals, then yes, absolutely!
They are being discussed independently and neither of them are currently approved by a DAO vote. SEP-2 seems to be much closer to that (currently in late phase 1) while the constitution proposal has just been put up for discussion (phase 0) and is not even an official SEP yet.
With my previous comment, I just wanted to raise awareness here for the constitution proposal and encourage everyone to review whether they think that SEP-2 would be in line with the constitution (in its current form). I personally think so but everyone should make up their mind themselves.
Strictly speaking, the constitution would arguably only apply to proposals and other activities happening from the time of when it passes a Snapshot vote, not retrospectively. Although practically speaking, we’d probably want to make sure that any SEP that passes before the constitution does is already aligned to avoid contradictions in the future.