Modern invented name, likely a variant of Jason or Chace
Chaysen is a contemporary American invention. It most likely functions as a phonetic blend of the name Chase and the popular 'son' suffix, or as a creative spelling variant of the name Chasen. It follows the modern trend of adding 'y' to traditional sounds to create a unique identity.
Less common today
Chaysen isn't in the latest US Top 1000. It last peaked at #5,909 in 2015.
US births per 5-year period, 1990βpresent (SSA data).