iPadOS (Beta) has 2 UAs.

User Agent in Safari on iPadOS |Apple Developer Forums

current result

ua-parser-js 0.7.20

UA: ... (Macintosh; Intel Mac OS X 10_15) ...

os: {
  name: "Mac OS",
  version: "10.15"
}

UA: ... (iPad; CPU OS 13_0 like Mac OS X) ...

os: {
  name: "iOS",
  version: "13.0"
}

expected result

os: {
  name: "iPadOS",
  version: "13.0"
}