The Summer Alter Ego Extravaganza (07/21/2021)

Is there any point in this event? I came back from an 8 year break last month and I have all of these trusts already, and last month was the first time I've ever collected any trust magic. So are these all availibe elsewhere?

Certain trusts can only be obtained at certain times. Valaineral Joachim Tenzen Mihli they give you in the ROE.

There is a minor point in collecting them all(*)most you can make them slightly stronger with a quest series after you have most of em.

Noillurie
Elivira
Lhu Mhakaracca
Ferreous Coffin
Gilgamesh
Kukki-Chebukki
Margret
Leonoyne
Maximilian
Kayeel-Payeel

Can only be obtained twice a year during the campains summer and winter. If you already have them, then there is nothing to do. (some of them might be on pells)

No idea how I have them all then, as I only came back last month, unless they coincided with one of the free weeks last year and I just don't remember buying them

Yes. Very much so to the point about the free-to-play. They often have come up to coincide with the "Return To Vanadiel" program, but it's not always a given. SE likes to bounce around their Free-to-play weeks a bit mostly because either Covid f's things up or they introduce a Mog Bonanza and don't want people buying marbles at one point to let their accounts lapse just to collect the goodies at a later point (which I believe is why we will not see a free-to-play until at least the collection period on Bonanza marbles is up).

If none of that makes any sense to you since you have only recently returned and you find you already have all of the trusts in the list, carry on. This set of trusts really doesn't have much standing out for it. The alternating trusts on the set that will be out in another 3 months has much better trusts. Wish the sets were balanced out more, but if you play for more than 6 months, you should have all of them from both sets.