Self-scans reveal that Pegasus, an invasive and powerful spyware that can secretly control phones and track owners, might be more widespread than previously thought. It was discovered on the phones of everyday phone users.
From wikiHow: How to Check Your Smartphone for Pegasus Spyware
I don’t think I saw it mentioned but if you’re already running/subbed to bitdefender av then you can install that on phone to detect it.
https://www.bitdefender.com/consumer/support/answer/1775/