jq ' with_entries(select(.key | contains("label")))'

cat data/ann.json | jq '.metadata.annotations ' cat data/ann.json | jq '.metadata.annotations | with_entries(select(.key | contains("label")))' 
{
  "deployment.kubernetes.io/revision": "1",
  "machine.openshift.io/owned": "",
  "label1": "stam",
  "label2": "another",
  "label3": "one"
}
    
{
  "label1": "stam",
  "label2": "another",
  "label3": "one"
}