According to the minecraft gamepedia, "In Bedrock Edition and Java Edition 1.14, Villagers can change their profession." but this does not seem to be the case.
I am playing pre-release 5 with my friend in a LAN server and we have an abundance of fisherman villagers. This seems to be due to two specific problems.
First of all, our villagers have claimed workstations that should not be possible to claim. They seem to have detected and claimed barrels in a bunker well over 30 blocks down underground. I assume this is a bug, as I've been told that villagers are only meant to claim workstations within eyesight.
The second issue is that these fishermen refuse to switch to different professions. We've not even interacted with them yet. let alone traded, but they remain in their profession even after the barrels are removed and new workstations placed elsewhere. Even more interesting is that the fishermen are within eyesight of unclaimed cauldrons and grindstones, yet refuse to claim them.
Comments 2
I had cured zombie villagers change profession after trading with them (I had a cleric, a farmer, a cartographer and a leatherworker); all were trapped in dirt on all sides while I built a fence around my house because they kept wandering off into the night. When I finished the fence and let them out, all were leatherworkers. Before curing the zombie villagers, I had a cauldron in the house at ground level, and a loom, cauldron and a potion stand underground, inaccessible to the villagers. (Note 2 cauldrons and 1 leatherworker resulted in 4 leatherworkers.) I have since broken both cauldrons and spammed the place with 7 compost bins, 1 lectern, 1 blast furnace, 1 stonecutter, 1 grindstone, 1 fletching table and 1 smithing table; the original loom and potion stand remain where they were. I have no smoker. One villager changed to a fletcher, the others will not change. (xbox one)
The barrels need to be broken in order for the fishermen to look for different jobs. The other bug is MC-148733.