In CreoleLingo - "ansyen" is listed with the definition of "old" and "ancient" can it also mean "former" or "previous"?

Yes, definitely.
It can translate former, previous, ex
as in
1.
ansyen mennaj mwen
my ex-boyfriend
my ex-girlfriend

ansyen madanm
ex-wife

ansyen mari
ansye mouche
ex-husband, ex-partner

2.
ansyen prezidan Bill Clinton
former president Bill Clinton

3.
Ansyen prezidan René Préval ap vizite lekòl la jodi a.
Former president René Préval will visit the school today.

4.
Mwen renmen nouvo òdinatè yo fèk enstale nan lab la.  Ki sa yo fè ak ansyen yo?
I like the new computers they just installed in the lab.  What did they do with the previous ones?

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