tl;dr - You should be using direnv to load ENV variables dynamically per-project. You don’t necessarily have to buy into the entirety of the 12 factor app manifesto, but you should almost definitely be using ENV-as-configuration by this point. Even if it’s just a CONFIG ENV var that points to a config.toml that your application reads, passing configuration via environment variables is the tried and true method of configuring applications these days (inside a docker container or out).
