One thing that is highly obvious is that to defeat Lucius alot will be needed.

Obviously Yuno will master his new magic, then gain the last spirit weapon. Along with one more thing. I think that Yuno will go beyond the limits of how far humans go with Mana, given how Mereoleona nearly disappeared after she got too close.

For Asta, now I think that he will make full use of his anti magic arm.

I think as of the moment he gave it up, he gained his own source of anti magic. His right arm. Liebe literally said the right arm became power itself, not like how when he simply trickled power into it.

I think this will contribute to to Asta's final power up.

I think Asta will be able to form his swords into one.

Asta having his own anti magic arm will make it more usable. Cause think about it, each of these swords in some way shape or form were clearly created to fight devils. Would the final form of such swords not have some sort of anti devil restriction, in order to keep such a power out of their hands?