E' vero, ho verificato.
"Finally, the two associations whose affiliated clubs achieved the best collective performance in the previous season of the UEFA men’s club competitions (i.e. best season club association coefficient), in accordance with the season coefficient principles (see Annex D.3), are each entitled to an additional place in the league phase, known as a European performance spot (EPS). The EPS is allocated to the club that finishes the relevant association's domestic championship in the highest position of all those that do not qualify for the league phase of the UEFA Champions League via the domestic championship (after any vacancies have been filled in accordance with Paragraph 3.04 to Paragraph 3.06). The two associations' overall quota of clubs qualifying to UEFA club competitions are each increased by one club."
Confermato: se una tra Atalanta e Roma vince la coppa arrivando quinta, prende il posto dell'EL Title Holder, toglie un posto italiano in EL e "libera" il sesto posto italiano per un posto in CL via EPS.
Quindi, in questa situazione:
5. Atalanta*
6. Lazio
7. Roma*
Se l'Atalanta vince la EL: Atalanta e Lazio in CL, Roma in Conference
Se la Roma vince l'EL: Atalanta e Roma in CL, Lazio in EL
Se nessuna vince l'EL: Atalanta in CL, Lazio in EL, Roma in Conference
* discorso equivalente in caso di Atalanta e Roma a posizioni invertite ovviamente.