from time import perf_counter
from PySide6 import QtCore, QtGui

app = QtGui.QGuiApplication([])

qimg = QtGui.QImage(100, 100, QtGui.QImage.Format.Format_ARGB32_Premultiplied)
qimg.fill(QtCore.Qt.GlobalColor.transparent)

niters = 10_000

t0 = perf_counter()
for _ in range(niters):
    px = QtGui.QPixmap(qimg)
t1 = perf_counter()
print(t1 - t0)

t0 = perf_counter()
for _ in range(niters):
    px = QtGui.QPixmap.fromImage(qimg)
t1 = perf_counter()
print(t1 - t0)