MULTI-TRAD explores register variation in machine translation, human translation and post-editing in texts produced by organisations in the Third Social Sector. The project adopts a corpus-based and multidimensional approach grounded in register theory and translation studies, combining corpus linguistics, multidimensional analysis and neural machine translation. The study is based on the analysis of a parallel Spanish–English corpus including original Spanish texts, human translations, machine-translated versions and post-edited outputs, which allows for systematic comparison across translation modes.