The Bible is very clear that god gives man purpose, but it is up to us to find it through our relationship with god. The deeds we do, and reflecting on our character. In other words, our purpose isn’t something we actively seek, but something we discover and learn throughout life. Something that would still be very possible in this scenario.
Purpose is tied to personhood, not origin. Just because you’re a replicant or brains scan does not imply that you are not a person if you’re capable of loving, hating, hurting, question etc. if someone can seek meaning, they can seek god as by being a creation of man they are still part of God’s creation and God’s ultimate plan. As Romans 9:8 so cleanly states:
It is not the children of the flesh who are the children of God, but the children of the promise are counted as offspring.
While contextually this explains they you don’t have to be related to Abraham to be in God’s grace, you just have to be able to seek god and live morally by him, it can be further taken to imply that anyone capable of seeking god in earnest is welcome in God’s plan and has a purpose.
And as a nexus 6 replicant, or a brain scan, they’re able to have full thoughts, dreams, hopes, and humanity, and thus can seek out God, which means they’d be welcome in his grace and would be able to find purpose.
Theologically you could argue that Deckard, as a replicant with full humanity, was given the purpose of rescuing Rachael and bringing the criminal Nexus 6 replicant’s to justice. Meanwhile Rachael’s purpose was to inspire Deckard to realize that there is humanity in a Replicant’s life and lead him to save her in the end. Two artificial humans given purpose by God due to their clear humanity.
The same argument could be made through Pomni’s actions in this finale serving as someone bringing the others together and keeping them from being lead astray like Jax was.
Of course, Goosworx 100% has no grasp of these concepts and likely has never opened a bible bun his life. And it’s frankly so disgusting to even bring a theological angle to this that I will most certainly have to repent, but the point still stands that if you were truly a religious person, discovering that you were never a true human wouldn’t inherently exclude you from God’s grace and doesn’t imply that you lack a God given purpose. If anything, your humanity and sentience would be a high indicator that God does indeed have a plan for you.