The easiest way you can save the transaction date in UTC timezone and for every user they can input their timezone in their profile which you save it in the database, thus you can output any transaction date in specific user’s timezone. This would work only when the user is logged in, otherwise you can just show the date in default timezone set by your application.
Another way -it’s quite easy too I think- is using javascript to convert the transaction date (which is in UTC like first one) to user’s timezone on the web browser. There is some javascript libraries to do this, I can’t recall the library name but just google it or search for it on github.