CrossEdge
I usually hate multiverse novels because they always end up braindead pokemon collectors(pretty much every multiverse novel is like that), even thought every single one has so much potencial. This is one of the few that have an actual likeable story(even if it is harem, don't decide on too many girls it will ruin it, he will already have 4, I think thats enough(I know its a DxD world but still)). I am also a big fan of Overlord, so the fact that you included Ainz and the other in this, brings me joy.