The bug
In Java Edition, copper golems turning into statues is instantaneous and guaranteed when the conditions are met (golem is aged enough, inside air, and near the center of its block space). In Bedrock Edition, copper golems can be delayed from turning into a statue multiple seconds.
How to reproduce
Run
/execute align xyz positioned ~1.5 ~ ~0.5 run summon copper_golem ~ ~ ~ 0 0 minecraft:from_player_oxidized
Expected results
The copper golem should turn into a statue instantly
Observed results
It takes several seconds for the golem to transform
Notes
You can contrast this with Java Edition. The command is /execute align xyz positioned ~1.5 ~ ~0.5 run summon minecraft:copper_golem ~ ~ ~ {weather_state:"oxidized",next_weather_age:2L}
Can confirm