Rogue One for me was the story of a girl who ended up joining the rebels, whose father worked on the Death Star project against his will, and she and the rest of the rebels were trying to get the secret of the Death Star's "Achilles Heel" to someone who could do something useful with that information. I remember Forest Whitaker was in it, and Donnie Yen played a blind Chinese guy who was seemed force-sensitive and had a great line about the Imps blindfolding a blind man. Oh yeah, there was a computer-generated Tarkin in it, and the ending had Darth Vader and dovetailed nicely into Episode 4, the original Star Wars, with Princess Leia turning out to be the "someone". Other than Jyn the girl, the rebels in Rogue One honestly all kinda blur together; I don't remember any other names or even much about their faces.
When I first heard of Andor, the series, I thought it was a planet and that the series would be all about stuff that happened on that planet during the Imperial Occupation. Which is also a kinda cool idea and not too far off from what we got. I was probably getting Andor getting confused with Endor, the planet where the Ewoks live. I didn't remember Andor the character at all, or any of the others including Melshi.
But I've been following the series discussions here and on a few other boards, and have a huge appreciation for what they've done here. The storytelling, acting, and production and effects have all been terrific.