Hunter Kid wrote:

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What did Happosai look like when he was young?

Most likely somewhere in between his own version of himself (extremely
handsome) and Cologne's version of him (short, ugly, just younger).  I'd
put him as a plain looking guy, not exceptional in any way except his MA
training...

In the Viz translation of the manga where Ranma learns the Hiryu Shoten Ha,
the 100 year old wanted poster for Happosai looks suspicously like Cologne's
version, so I would say her's is probably more accurate.