I want to get a tattoo of the words "free spirit" in Latin. Can someone help me find an accurate translation of those words?

'solvo phasmatis' is the translation of free spirit, it may not look as attractive as you thought

In spanish its 'espiritu libre'

I too get, solvo phasmatis as the translation.

Anima Libera (nom.sing) is the correct one.
Solvo phasmatis is a "non correct" translation. Phasma,phasmatis could be "spirit", but it's a Late Latin concept rather than a Classic one. The verb solvo,is,ere,-vi,solutum (unleash) doesn't have a direct semantic relation with "something free" per se, so you have to use an adjective rather than a verb. The adjective "liber,liberi" makes more sense because it means "freedom." Ancient Romans had 2 distinctions between objects: the animated ones and the unanimated ones. Humans and nature were animated, objects weren't. The Latin word for soul is "animus" which means "breath, soul, spirit", like in Greek αἰθήρ (aither.)