Community manager Trikslyr confirmed some upcoming changes to these two heroes, including a change to the newest battleground, Braxis Holdout.
Machines of War is bringing loads of content and balance changes to the Nexus with an emphasis on revamping some of the oldest heroes where they need it most. Nazeebo and Chen are completely reworked in the current PTR and most people agree that the changes are positive (though Nazeebo is still up for debate), however, Tychus and Valla fans have made their concerns known on the battle.net forums.
Their fears were put to rest with these official responses from Trikslyr:
B.net forum post on Braxis Holdout:
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