Honor Points and Conquest Points as currencies have removed in Legion Pre-Launch. Low-level PvP gears no longer costs Honor. It requires Mark of Honor instead. Honor Points in 7.0 is the equal of experience to upgrade Honor Level, then to unlock more PVP talents and Artifact Appearance.
Players can earn Treasure Chests reward from Battlegrounds and Arenas, and gain PVP gears and Mark of Honor from the Treasure Chests. Mark of Honor can be used to purchase PVP gears, weapons, mounts and heirlooms in past expansions. 
You can buy all Warlords gear in bulk as a weapon Arsenal or armor Ensemble, or older sets piece-by-piece. It is cheap to buy some PVP gears(S16-S18) by packages, say buying PVP gear piece by piece will need 19 Mark of Honor totally, while 12 Mark of Honor required if in a package; purchase all weapons need 135 Mark of Honor, while 80 Mark of Honor required if in a package. 
It is an excellent opportunity for transmog set enthusiasts to collect all PVP gears. 
Tips: Mark of Honor is Binds to Battle.net account, suggest to make a warrior to receive all Mark of Honor, and to purchase most of weapons and gears. In this way, you can unlock the weapon and  PVP gears for all of your classes.