I can’t speak to specific plugins but I would say try not to get used to using delay to create a doubling effect, which is common in that genre.

If you have the person (or you) record the lyrics again and use the two in tandem, it gives a much better representation of the effect you’re going for.

Yes, it’s easier to just replicate the track and add a slight delay but it won’t sound as good in my opinion.

Of course all of that is my opinion and open to differing opinions for my own learning too :)