Sandman vs Dust
the super criminal Flint Marko vs the ex Afghani Slave Sooraya Qadir
(im not actualy sure how this will play out.
One turns into a sandstorm the other is sand.
you guys can fight this one out[also im not sure if im pulling this out my arse but i remember reading that a mutants control of their powers is stronger than a superhumans{i could be getting this from the fact that mutants and and superhumans need different power dampeners}again i could be pulling this out my arse]ciao)
Dust had high pressure/velocity control shredding flesh with her sand ability but flint had more overall control of a wider area of sand (sand absorption/mass control) had shapeshifting ability (making maces, multiple clones which he had control of eachs 'motor functions' if you'd call it that) could fly as a sandstorm and developed superhuman qualities like super strength (I think he is on things lvl more or less)
This is really a matter as if flint can absorb her and overpower her consciousness. Otherwise I'm not sure they can damage one another in sand form, if anything as she throws sand at him he will absorb it taking from her mass unless she can pull her sand particles out of him. Flint has had his powers alot longer so I'm not sure if her mastery of her powers are anywhere near his.
If she exhausts herself and go flesh then he has her at his mercy.