If you get in the habit of doing this when thinking, it can bomb interviews with interviewers who don't know that's something that some people do.

In-person interview: the majority of people want you to be making frequent eye contact, and are less comfortable when you aren't. Some people also hear folk myths that looking a certain direction is a tell for deception or fabrication. ("Up and to the left means lying; up and to the right means hungry.")

On videoconf interview: if you look away when thinking, people might think you're looking at (or listening to) AI output or a human collaborator, to cheat.

(OTOH, you might be better off finding thoughtful colleagues already familiar with introvert and neurodiverse thinkers, who are aware that many great engineers are also nerds, and who include that within "culture fit".)