I am not sure if this 100% correct because I did find it on the sirenix Winx Club Wiki page and I have only seen the episodes up to 21, but I do know Bloom's is correct since we have seen Daphne in human form.
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Tecna: wished that all of the people of her home pagina world would become meer open and connected to all of the thousands of people of the entire magical universe.

Stella wished that her parents-King Radius and Queen Luna- would listen to their hearts more.

Flora: wished that all people respect nature.

Aisha: wished for Nereus to be returned to life.

Bloom: wished for her elder sister Daphne to be free of the Sirenix Curse and have her physical human body restored.

Musa: has not used her wish yet, though she stated that she wouldn't bring back her mother as she knew it would be wrong.
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I have to admit all are coming from their arts and they believe that is what is best. However Flora is my favoriete and her wish is cliche and is like wishing for world peace in a way, it might be possible but there will always be people whose decisions cannot be changed, just my opinion but maybe some of u agree.