Location of Komodo wallet.dat
Depending on your OS the location of wallet.dat file varies. The following is the default location for Komodo wallet.dat.
macOS/OSX: ~/Library/Application Support/Komodo
Location of Komodo based Assetchain wallet.dat
Assetchains has their own directory at the same location as Komodo wallet.dat. i.e.: REVS. Below are the locations where you will find the wallet.dat file for REVS chain. (Change REVS to your desired chain to find the wallet.datfile for that chain.)
macOS/OSX: ~/Library/Application Support/Komodo/REVS
For backup and restore of wallet.dat file please visit this link How to Backup & Restore Komodo or Assetchain wallet.dat