Going from Hausa to Malay (Bahasa Melayu) has a composite linguistic distance of 73% (heuristic estimate). Below is the dimension-by-dimension breakdown.
Shared vocabulary, cognates, and loanwords.
Morphology, syntax, word order, cases.
Shared sounds and phoneme inventory.
Latin/Arabic → Latin/Arabic
Afro-Asiatic ↔ Austronesian
The 5 languages with the lowest linguistic distance from Hausa:
A quick 3-question check between Hausa and Malay. No signup.