That is my name :) but the French part of my family calls me Léontine.I’ve only ever gotten compliments for my name and the name travels fairly well. The amount of nicknames makes the name versatile :)
This is a very beautiful name. It's strong and feminine and also kind of soft and elegant. I also adore Léontine, but I think Leontina is more usable today (in English speaking countries).
I think it's more correct to say that Leontina is a feminine form of Leontinus, because the -ina part clearly refers to a diminutive form (so it's not just a 'femininization', because a mere 'feminization' of Leontius would have been Leontia).