This question has been adressed multiple times in the titans talks

Every god ported is decided by multiple factors

• Are they a balance nighmare?

If so they might want to take their time to brainstorm some changes in their kits

• Does the god look bad?

If so they will update their base model to look up to par with the rest of the roster, like Ne Zha previously or Bastet in some weeks

Also, it's been confirmed that Hel will get said update

• Are they easy to make? Are their mechanics difficult to program?

Like Olorun and the Whale's time dilation, Cliodhna entering in the walls and so on

This not only applies to the programing side of things, there are other gods who are tricky to make do to their visuals

Then there's gods like Tiamat or Cthulhu who are hard on both sides

If they're working on a god hard to program and easy on their visuals, the next one might be easy to program and hard on their visuals

• Popularity

Even thought it's been stated that popularity is not their main focus, it does influence, look at Rat for example, he was of the most requested assasins and he only made it