Dutch: materieel recht
English: substantive law 
Spanish: derecho sustantivo 
French: le droit matériel

Spanish: ley sustantiva
Dutch: materiële wet

(https://www.proz.com/kudoz/spanish-to-dutch/law-contracts/2033123-ley-sustantiva.html)
materiële vereisten
material requirements (e.g. in the context of manufacturing processes)
substantive requirements (e.g. ‘the substantive requirements of patent applications’: https://www.epo.org/law-practice/legal-texts/html/guidelinespct/e/g.htm)