So what if someone within the Star Wars universe makes a biopic about Han Solo? They could use excerpts of his spinoff as a movie-within-a-movie. Kind of like the Stab movies in the Scream franchise.
Think of all the problems this would solve. Ehrenreich wouldn't have to look like Harrison Ford anymore, because in the world of the Star Wars saga, he'd be an actor -- which is probably one of the few jobs available if you don't like bounty hunting or stormtrooping. That wacky comedic tone, more suited to rescuing quarterbacks and dolphins than gunning down lizard people in seedy bars, wouldn't be a problem. The gulf between the new iteration of Han Solo and the original would suddenly become the focus, not a liability.
Now, you might be wondering: Do they even have movies in Star Wars? They do, and they're called "Holodramas". According to Wookiepedia, they're "a form of fiction entertainment created using holographic technology." In the recent Rogue One prequel novel, we learn that a young Jyn Erso had a "favorite bedtime holo." Yeah, looks like Star Wars characters don't have to read books to their kids; they shove holograms in their faces at night.
We've even seen these holographic movies before, back in The Star Wars Holiday Special. Remember how Chewbacca's poor neglected son fills the void his dad left behind by watching this terrifying video from the Cirque people of the Du Soleil planet: