Rezzed the wrong thread earlier (my apologies mods), Rathnard keeps his more up to date, A couple updates:
Some more Meridian info on https://www.wyrd-games.net/news/2017/6/23/qpd75lr9isu0rqhljjd4kk5b3nc3v0
Meridian is still Malifaux-side, imprisoned in the ley lines and voice carried by the ocean currents. Also confirmed as a "She"
Also of note, at least towards other powerful entities if not a tyrant itself, but something powerful slammed from Malifaux into Mount Etna thousand of years ago.
https://youtu.be/wF9VyyRheWY?t=36
Speculation: One of our missing Tyrants? Shez-uul? signs point to Shez-uul being trapped earth side, though that means at some point he would need to wake up and traveled from Italy to Japan.
However Thousands is a vague and long timeframe, I don't know if we know how far back Titania's war with the Tyrants was, timelines might not match up to make sense for it to be a Tyrant. Though some examples of time magic also exist withing Malifaux so who knows.