OroPlatform: custom environment variables to .env
OroPlatform doesn't use dotenv files for now. The platform is based on Symfony full stack framework, but there are some differences.
Instead of .env, defaults for environment variables are defined in the config/parameters.yml and config/parameters.yml.dist files. See https://doc.oroinc.com/backend/setup/dev-environment/parameters-yml/ for more details.
Anyway, you can use real environment variables and parameters.yml replaces .env when you want to emulate them locally.