I have 3 villagers that roam the basement of my house in my survival world. 2 librarians and a toolsmith. I had one lecturn, one smithing table, and one fletching table. I removed the lecturn and smithing table to help show the bug.
My villagers were turned into zombies, and when i cured them, my toolsmith started working at the fletching table, and one of my librarians started working at the smithing table, both without changing their profession. They even refresh their trades at the wrong workstations.
In the screenshot, the subtitle says toolsmith works, even though he's at a fletching table. i only have 3 villagers, and no other workstations down.