They can have the same word or sentence, or different words in opposite directions.
Serena requested this ambigram where her name, when rotated, becomes the name Andrea.
For professional use or plain funRelated tattoos:

Ambigram

Ambigram

Love and soul ambigram

Ambigram

ambigram

Ambigram

Ambigram

Ambigram

Ambigram

Ambigram

Ambigram