Popular in the 90s were only maybe
Susanne,
Karen and
Elisabeth, though none of those were actually considered fashionable back then.
Heidi has only recently become popular and
Liesl and
Gretel were never considered actual names but diminutives that haven't been in use for a hundred years or so.
Kunigunde and
Meta are totally outdated.
Here is a link to names popular in the 90s:
http://www.beliebte-vornamen.de/3778-1990er-jahre.htm.
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