Domain adaptation remains a major challenge for machine translation, par-ticularly in institutional communica-tion. This paper presents the MULTI-TRAD project , which develops English–Spanish parallel corpora for the Third Social Sector communication. The project integrates three comple-mentary objectives: (i) the compilation of a domain-specific parallel corpus, (ii) the analysis of linguistic variation across human translation (HT), ma-chine translation (MT), and post-edited (PE) texts using Multidimensional Analysis (Biber, 1988), and (iii) the development of a domain-adapted neu-ral machine translation system. In par-ticular, the project investigates how dif-ferent translation processes give rise to distinct functional profiles, related to phenomena such as translationese and post-editese. This paper presents the project design and initial progress.