As long as you use standard serialization, and don't use serde_bytes, then the serialization output will be a valid string (utf8, not binary).
If you are using string &str or byte &[u8] slice in your resulting structure, it will not be copied (Zero-copy).
You can try encom_from_json!() macro to convert your own JSON and test it. Resulting EnCom will be sorted alphabetically.
#[serde(serialize_with = "path")] is passed, then serialize None} in serializer