In Estonia we have personal codes and therefore don't really have problems with name changes, but by default our personal codes infer sex and birth date, which would be very problematic in your case. Basically you would have to 'write support' on every other site to get old accounts back. I think neighboring Latvia went with random personal codes now, so essentially they have something closest to your 'stable uid'.
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In Estonia we have personal codes and therefore don't really have problems with name changes, but by default our personal codes infer sex and birth date, which would be very problematic in your case. Basically you would have to 'write support' on every other site to get old accounts back. I think neighboring Latvia went with random personal codes now, so essentially they have something closest to your 'stable uid'.