Fides rhymes with:
confides, abides, asides, besides, bride's, brides, chides, coincides, collides, confides, decides, derides, divides, glides, guide's, guides, hides, hyde's, insides, lapides, misguides, nationwide's, outsides, presides, prides, provides, resides, rides, side's, sides, sides', slides, strides, subsides, tides, wide's
Fides sounds like:
faddis, faddish, fades, fads, faiths, fates, fatigue, fatigues, fats, fatties, fatuous, fauteux, fayed's, feats, fed's, fedak, fedex, feds, feeds, feith's, feitz, fetch, fetches, fetish, fetsch, fetsko, fettes, fettig, fetus, fetuses, fetz, feuds, feutz, fiat's, fifths, fifties, fifty's, fitak, fitch, fites, fits, fitts, fitz, fitzco, fitzhugh, food's, foods, foods', foodways, footage, foote's, fotis, foutch, fouts, foutz, fudge, fudgy, futch