So where does SM take place in the timeline of this realities games? (SM/XY/ORAS take place in another dimension to all games prior)

I think definitely after XY because we have Zygarde research happening, and looker is fine in those games.

In ORAS, looker is washed up on a beach with few remaining memories, like Anabel's backstory for this game. Anabel remembers "defending a tower" which refers to the RSE battle tower, which hasn't been constructed in ORAS.

Looker is also fine in SM.

Zinnia says something about what if the alternate dimension didn't have the technology to stop the meteor, and they don't. You had to use M-Rayquaza to stop it, there are no megas in the RSE timeline.

My theory is that the ORAS looker and the SM Anabel are from the original timeline of RSE, which was destroyed by the deoxys meteor.

So with the lack of postgame stuff in ORAS, we don't know if this timeline has an Anabel, but I think we might have two lookers, one of which is from the RBY/GSC/RSE/DPPt/BWB2W2 timeline.

I want to get this all sorted out with theories before I even start thinking about what the fact that we can travel between the sun and moon dimensions means.