Showrunners are definitely trying to keep the season two storyline a secret, which is probably why they haven't disclosed much information about new characters. However, according to Deadline, during a panel at New York City Comic Con, showrunners revealed that actor JJ Feild will be playing Ben Adler, an advanced systems and artificial intelligence expert who is also Maureen's academic contemporary.
That Hashtag Show reported that there may be two other new characters — Ava, a "firm, hardworking, and serious" mechanic who "shuts down Don's nonsense but respects his skill," and Commander Jiang, who is described as a "capable, stalwart, and unsentimental" Captain of the Resolute.