Do you think that some translations may not need language editing?

Standard EN 15038 does not use the term "language editing", but mentions "revision" as a compulsory step in the translation process.

Regardless of the language editing – which can be either undertaken as part of the translation process or carried out later – the translator’s competence is crucial; however, the quality of the translation is not guaranteed by the translation (which is just one phase in the process) but by the translation being reviewed by a person other than the translator – the reviser – and secondly, the professional competences of each of the participants in the translation process, mainly translators, reviewers, revisers and proofreaders.

The reviser is competent in both languages and revises the translated text by comparing it to the original source, informing the translator of any problems and recommending any changes needed.