Screenshots are from Wii U Edition.

Legacy fog is similar to beta fog in its intensity with distance. I was able to approximate this look in Console Aspects by starting Overworld fog at 40% of render distance and ending it at 90% (meaning the chunks between 90 and 100 were fully shrouded in fog). End fog is even more intense, starting at the player (0% of render distance) and ending at 80%.

Finally added in version 1.5.1, thanks for reporting

There's a problem with the End fog with Sodium installed. It's a gray fog now, it's bad... Not a related Legacy4J issue.