Abilities:
Versatility: Han has far more options, tough some of Ragna's abilities seem really OP.
Martial Arts and Weapon Mastery: Don't know ragna enough to say who's better, but both have this. Han gets speed amps if he uses this tough.
Regen: Both have it on a similiar level. Gonna point out that Han's "regen" is less about healing and more about damage on his body being registered as HP decrease. He can heal, but I'll get there later.
Immortality: Welp, Han will need to incapacitate. He has several ways to do so, but this depends on Ragna's resistances (more about that later)
Enhanced Sense: Both have it, but Han's seem better (can sense bloodlust, has a sixth sense for dangerous instances and observe allows him to see the enemies stats)
Forcefield Creation: Both can do it, Han's been shown to be passive.
Stat Amping: Han's seems far more easy to activate anduse.
Soul Manip: Yeah, this will destroy Han if he gets hit. Not one-shot, but still.
Existence Erasure: How is it activated?
Now the deciding factors:
Healing and Healing Negation: Han's healing is described as being above cause and effect, would it still be negated?
Resistance to mind manip: How good is it for Ragna.
Golems: Han has 100+
golems, that could change plenty of things.
In-character action: What does Ragna start with?