Self-explanatory. I think from time to time about how hard it is for actors to end-up on one hit, much less two. But quite a few have (playing a bit fast and loose with "star" and "hit" on a few of these).
Michael Weatherly - NCIS, Bull
Tom Selleck - Magnum P.I., Blue Bloods
Kelsey Grammar - Cheers, Frasier
Ted Danson - Cheers, The Good Place
Julia Louis Dreyfuss (she's the only one I can think of in more than 2) - SNL, Seinfeld, Veep, New Adventures of Old Christine
Tim Allen - Home Improvement, Last Man Standing