When asked about new Items, League of Legends developers replied with "We are working on two new items and one heavily reworked one. Ideally at least two of these will make it to live during the summer; the third one we’re not sure about yet, as it may slip to preseason."
The first of these three items is a new Legendary tank items. The plan for this one is for it to have a binding, like Knight's Vow and Zeke's Convergence, but the bind is with an enemy rather than an ally.
The item will grant damage reduction against that targeted enemy, as well as tenacity reduction against them when near them. This will give many new options when players need to focus on a single threat, whether it be a fed carry, single-threat composition, or a split pusher.
The second item will be for split pushers. This is a reworked Sanguine Blade, where they're keeping the idea but changing the stats.
While little information is given, it is being taken out of the Lethality space so it can appeal to any AD Champion.
The power will be shifted so it continues to focus on 1vX potential, which is more SoloQ focused, but will also give power to taking a tower against durable opponents, which is more pro focused.
The plan is for this rework to ship alongside the Legendary tank item, as they will interact with each other as well as being top lane/split push focused.
The final item in development is an Enchanter Support Legendary item.
This item is to help shore up some of the Enchanters weaknesses, being squishy and therefore easy to punish if caught out. This new item will provide defences similar to Zhonya's Hourglass, but with a more supportive identity.
While covering a clear weakness of Enchanters may allow for no counterplay, making them too safe and strong, I'm sure this is welcome news for Lulu mains who are tired of being hooked and burst constantly.