Same here. I changed nothing about Cubase or my OS (Mojave). If I try to open a session through the Steinberg Hub window, it will crash every time. If I cancel that window and then click the session file directly, it takes 3-4 attempts. Would love for this to be fixed soon.
As no one from Steinberg answered me, I would like to tell you what just worked for me: Activating ASIO Guard on highest level, while decreasing my interface buffer size. Try it and hope it works for you.