My recommendation would be God of War (2018). Haven’t played Ragnarok yet, so I can’t talk about that one. You really attach to the characters. Their personalities are well defined, and it presents some father/mother/son dilemmas along the journey. Great OST, too.
I know it’s not known as “emotional,” but it’s the only game I recall that made me cry a little at the end,
I don’t think playing previous GoW games is mandatory. A quick recap is enough.