PVP players love PVP, PVE players love PVE.
So why does a PvP player need to go to PvE, and a PvE player doesn’t need anything - is he okay?
I suggest using the mechanics of World of warcaft:
In this PvE game, players clear raids to get good loot, kill NPCs and do quests to increase the level.
PvP players can instead fight in the arena getting special points for buying special armor and weapons that have a bonus in pvp, and they also gain experience for PVP.
Those. such a system provides an alternative to do what you want PvE or PvP.
But at the same time in PvE dungeons there are several items that are required for PvP players and vice versa (for PvP points you can buy something useful for PvE) - usually these are earrings with special buffs, or decorative mounts.
This makes it possible to trade between the two modes of PvE and PvP.
Why not do it too?
(This is just one example)
For example, enter 2 types of blocks - PvE blocks are mined in very complex POIs - have medium armor, very light, but most types of weapons will do high damage to such blocks.
Which makes it not a good choice to use these blocks in PvP.
In PvP Events, very strong, heavy blocks are mined along which the reduced damage passes.
Increase the number and variety of PvP events - similar to FPS.
So that such events take place every hour.
Events should not be limited in level - i.e. the players were on an equal footing - for example, both players were given the same weapon / equipment.
And for such events in the form of a reward, give a lot of experience - so that you can swing not only in PvE but also in PvP.
I don’t know if Rexus can add new items to the game, so I’ll stop here 
This is just a simple example, this idea can be developed endlessly - it all depends on your imagination.
(g.translation)