Incorrect, Itachi still has his eyes as an edo since he died while still having his sharingan, if he had died after having his eyes removed he would've been ressurected without them.
No, I don't know where you got that idea from... that was never stated. Why would Kabuto wan't to bring back Shisui then if he had no eyes? All of Kakuzu's hearts were destroyed so how was he brought back with them?
Kabuto says it himself. They are ressurected with all their abilities, including those afforded by the SO6P such as the Rinnegan. They are brought back how they died, but they have all of their abilities and Kekkei Genkais intact wether or not they died without them.