Hello,
i am currently using ca-easytrieve/Plus for os/390
Somewhere (probably near the top of the Ezt output) will be a number (i.e. 6.3, 6.4, 11 etc).
Near the top of the COBOL part of the forum is a Sticky titled:
2-file match/merge sample code
This contains working logic for what you want to do. You should be able to re-code that sample in Ezt using 2 input file definitions. This approach would not use any built-in function to match.