There’s the start of this going on here, for the history list/search commands: Allow specifying a timezone in history search/list by cyqsimon · Pull Request #1517 · atuinsh/atuin · GitHub
Once it’s in the config we can apply it elsewhre
Fwiw, we will always store UTC, but use the config file to change how it’s displayed. Everything is a unix timestamp (nanoseconds though) internally.