I just looked in the Corpus Diacrónico del Español https://corpus.rae.es/cordenet.html https://corpus.rae.es/cordenet.html and it found 33 hits for "phisica"

I just looked in the Corpus Diacrónico del Español https://corpus.rae.es/cordenet.html https://corpus.rae.es/cordenet.html and it found 33 hits for "phisica" and 99 for "phisico", mostly from the 1490s. Now some of these can be deceptive, like a few are from a bilingual Spanish-Latin book and occur in the Latin portions rather than the Spanish portions, but it seems like some authors in the 1400s wrote "ph" in some Spanish words, at least when they knew the Latin or Greek etymologies. I don't know when the Iberian languages first got their more phonetic orthographies, especially suppressing that h (that was originally in Latin digraphs used to transliterate Greek letters θ, φ, χ). Edit: There are also about two dozen hits for physico/physica, interestingly more from the 1700s rather than 1400s.