Zephyr is pretty meh but other than that, some other items that are pretty op are bloodthirster and dragon’s claw. If you include spatula items then all of them, and especially the glacial, blademaster, and sometimes the sorcerer and assassin are extremely strong.
It’s important to note because people don’t seem to know this: yuumi doubles your base mana regen, meaning 20 mana on auto or 30 on a crit, so it is actually better than shojin for any unit with less than a 67 mana cost. Between 67 and 40 mana, yuumi is the best mana item in terms of regen. Yuumi is still the best mana item tied with seraph’s down to 30 mana cost, after which seraph’s outdoes yuumi. Since it gives AP unlike seraph’s, it’s important to remember that that does make it better than seraphs at that level of mana. It is also worth noting that even though 67 is the mana where its mana gain is equivalent to that of Shojin, technically if we speak in terms of actual auto attacks needed to regain mana, yuumi is equal to shojin up until 80 mana. This is assuming that shojin passive is up from the beginning, stuff gets more complicated when you consider that shojin only takes effect after first spell cast. This also ignores the fact that this does not benefit sorcerers or elementalists, as both already have this buff active.