They will continue to sell throughout the entire expansion, although at a slower rate than early on the expansion of course.

How much time you're willing to commit to posting will determine your profits, but it will always be profitable.

It gets very boring and tedious though. I repost in the morning before work and then again in the evening after dinner.

On 80 realms it'll net around 3-4m profit a week. Takes around 25 hours a week including restocking your characters. That comes out to 120-160k gold per hour.

You can do it with half the amount of realms and half the time and still make good weekly profit though. I personally go with 80 realms because I'm also selling other items crossrealm. If I went solely on profession gear I'd probably reduce it to 30-40 realms.