The correct spelling is Freeza.
It is not Frieza.
This is the Funimation dub spelling. It is unnecessarily confusing.
It is not Freiza.
This is a misspelling of the Funimation dub spelling. It is exceptionally wrong.
It is not Freezer.
Some non-English translations use this incorrect spelling.
The Japanese name would elongate the final a sound if this was the intended pronunciation: フリーザー (Furīzā/Freezer).
It is not Furiza, or Furiiza.
These are direct romanizations. Only weebs use these.
And it is certainly not Fr- uh....
This spelling is an abomination and its use should not be encouraged.
The correct spelling is Freeza.
フリーザ (Furīza/Freeza)