I was testing out some conversion issues on Nintendo Switch and I was flying around a world and testing how some mobs transfer over. When I transferred it, I found that I couldn't change the mob spawner to any mob. It just stayed as it was (as a blaze spawner in the nether).

The seed for the world I tested it on was -5994147957692880292 on Legacy Nintendo Switch and the coordinates were X:11 Y:65 Z:58. The coordinates are for the nether.