How to create the appearance of an accent can be to some extent language specific, especially where a word in one language might use different consonants and vowels than an equivalent word in a different language. But as long as the general characteristics of accented speech are recognizable, this should not pose too big a problem.
Tako je govorio Lucio Fabiani: zima svoga života. S umekšanim suglasnicima, onako po talijanski, pa bi zima bila cima, svoga zvoga, život zivot, i čim bi Ćućo spomenuo cimu zvoga zivota oba bi mu oka bila puna suza. Ali ne onih koje niz obraze poteku, nego naročitih suza stajaćica, kakvih u to vrijeme u Sarajevu nije bilo, ni oko njega, na pašnjacima, među pčelinjacima, te su ih ljudi nazvali—suze talijanke, i čim bi netko u društvu spomenuo da su se kome oči napunile suzama, upitalo bi ga—je li talijankama, i svi bi tad znali o kakvoj se žalosti, o kakvom čovjeku, o kakvim se suzama govori.
Here the general characteristics of an Italian accent are what stand out, not the specific ways that it manifests itself in one or the other language. Since there is a comic effect as well, it needs to be relatively pronounced, it seems to me, and there aren’t enough consontantal markers in “winter of one’s life” for that, though “once” for “one’s” is a good start. Plus my author has every word accented. So I’ve added a bit to make it stick.
This was what Lucio Fabiani said: the winter of one’s life. With extra vowels and softened consonants, as in Italian, so that winter was a-winter, one’s was a-once, life was a-life, and the moment Ćućo remarked on the a-winter of a-once a-life, both his eyes would be filled with tears. Only not the kind that run down your face but that particular kind of stay-in-place tears that did not exist in Sarajevo then, or anywhere nearby, on the grazing lands, among the beekeepers, so people called them Italian tears, and anytime someone might remark in conversation about how another’s eyes had filled with tears, they would ask, Italian ones? And then everyone would know what sort of complaint, what sort of person, and what sort of tears were being discussed.
A-this is a-good for a-now.