Ah, PowerChute. It has been a few years but I'm at least minimally familiar.
I don't think Lansweeper can handle this scenario, or at a minimum it would get really confused if you did make it work. It's going to say [HOST] is [IP], but also that [UPS] is associated to [HOST], which is [IP]. Unlike monitors, I don't think it can interpret the UPS as attached to [HOST] and create a separate asset for it. They would likely battle for supremacy.
I don't think you would even get that far, but if you did I think your next post would be "Why does Lansweeper keep replacing my [HOST] asset with my UPS asset?"
If it's important enough, you may be able to buy an add-on card for the UPS to allow it to connect directly to your network.