For this site, I am noticing the font takes a second to load, so you see a flash of the default Times font before the sanserif loads.
I tried doing this:
But it didn’t do anything. Is this even solvable, or just something one has to accept?
Fonts are cached by the browser. There are different font loading techniques to prevent FOUT, which you can find by googling. The most important is to use a good font stack with standard fonts that are as close as possible to the chosen web font to prevent the most ugly effects.