Yes, there were alot of comparison pics of Momoa and 90s Jae Lee Namor posted when he was announced.
I just don't think it would be a Namor story if he was raised on land. Yes, that AU was a good story, but it's AU. 80 years of Namor stories revolve around him being raised undersea, privileged, yet never truly accepted. And on the surface, he's the alien, the Other-- the commentary on the craziness of our own culture, the magic or myth that is missing from it. At least they didn't steal that for the Aquaman movie.
There were a few articles at the beginning of the year. They seem to be progressing in a chronological fashion, for the most part.