New players in World of Warcraft do not have access to Chromie Time and must play through Battle for Azeroth before heading to Shadowlands. However, there’s currently a workaround to circumvent that.
Apparently, when the new player creates a Class Trial, it unlocks Chromie Time for all characters. At this time, we are not sure if this behavior is intended or a bug.
Chromie Time lets you pick the starting zone and the expansion for leveling in the 10-50 range. The feature is not available for completely new accounts who must first go to Exile’s Reach and then play through Battle for Azeroth before going to the Shadowlands.