History says every expansion has a brand new relic line unattached to the previous and uses new content from that expansion.

2.x had zodiac. 3.x had anima weapons. 4.x had eureka weapons. 5.x will have some new fancy relic quest chain unrelated to the existing ones.

If you want a 2.x weapon, you have to go back and do a buncha lv 50 quests. Eureka will stay the only way to get lv 70 weapons forever. They will just nerf the crap out of eureka one day so you can go back and make them when eureka is dead. (Probably uncapped ilvl, allow you to buy special items with crystals or something. Buff amount of light from everything etc) but it will still be eureka.

If you just want the glamour they will reuse the model later like they did for 2.x weapons with crafted items. They just want glow.