Very tough to decide but Valkyrie has the discipline or used to and still has the combat/training. Night crawlers abilities are very useful and he can use that to his advantage. In the end Nightcrawler’s a little boy with little experience. The battle goes to Valkyrie.

I think, I will go with Night crawler. His superhuman agility and power to teleport would make him indisputable when going against Valkyrie.

I agree with @raj mehta
Night crawler has abilities like superhuman strength, flexibility, teleportation, great at Acrobatics, hand to hand fighter, devil tail. Were Valkyrie got superhuman strength, durability, warrior fighter, swordsman.
In this way night crawler is more powerful than Valkyrie.

ill go with valkyrie

Both have different set of powers so theres no comparison