If aliens have bodies, they are not angels. If they are living, they have souls. If they are intelligent, they have immortal, spiritual souls.
If they exist, they would be like any other rational animals (aka physical persons) who were previously unknown, i.e., Native Americans, Aboriginal Australians.
If they were subject to Original Sin, and I don’t see how they could not be, they would be in need of redemption by God Incarnate. Just as redemption wasn’t limited to Jews, or Europeans, so it would not be limited to Terrans (Earth natives). If they were not subject to Original Sin, they would be in a state of original innocence, but still need elevation by grace through God Incarnate.
But since there is no real evidence for their existence, I have no reason to believe they exist, so these questions are moot. I am not impressed by the statistical argument: there must be billions of planets capable of sustaining life, so there must be intelligent life elsewhere in the universe. We have no idea how likely the development of life is in the universe. It might just be a 1 in hundreds of billions chance. I don’t even know what it means to calculate the odds. And without an accurate measure of the likelyhood of life, there is no way to speculate whether that likelyhood has been realized.