Wow, that's interesting. ^_^
Also I wanna see Charybdis as a Titan, we got Scylla so why not this,it's said to create whirlpools with it's mouth. (Posssible designs could be a dunkleosteus or either a bobbit worm.)
I've got many headcanon Titans of my own that also exists in the MonsterVerse.
-Titanus Anubis (Egypt)
-Titanus Burrunjor (Australia)
-Titanus Chupacabra (Puerto Rico)
-Titanus Dingonek (Africa; Lake Victoria)
-Titanus Emela-Ntouka (Africa)
-Titanus Fenrir (Scandinavia)
-Titanus Jersey Devil (New Jersey; Pine Barrens)
-Titanus Jormungandr (Scandinavia)
-Titanus Kasai Rex (Africa)
-Titanus Lusca (Bahamas; Blue Hole/Bermuda Triangle)
-Titanus Mbielu-Mbielu-Mbielu (Africa)
-Titanus Ogopogo (Canada; Lake Okanagan)
-Titanus Phoenix (Greece)
-Titanus Piasa (Illinois)
-Titanus Roc (Middle East)
-Titanus Sasquatch (Canada)
-Titanus Sobek (Egypt)
-Titanus Surtr (Scandinavia)
-Titanus Tarasque (France)
-Titanus Thunderbird (Missouri)
-Titanus Wendigo (Canada)
-Titanus Yeti (Tibet; Himalayas)
-Titanus Ymir (Scandinavia)
-Titanus Yowie (Australia)
Used to have Titanus Grootslang and Titanus Mapinguari but now like to think Titanus Mokele-Mbembe and Titanus Behemoth inspired those creatures of legend especially given the former's description in the novelization of King of the Monsters.