Advice about choosing legendary gems

Hi, i would like to apologize in advance if I’m not posting this in the correct section. Feel free to move it if appropriated.

I play Crusader, my focus is PvE and I’m just a Battle Pass buyer. To my immense surprise and delight, i just got a bounded Roiling Consequence 4*. My question is: What do i do now? I presently have:

Echoing Shade lvl3
Pain Clasp lvl6
Fervent fang lvl6
Viper’s Bite lvl6
Mother’s Lament lvl6
Everlasting Torment lvl10
Berserker’s Eye lvl10
Ca’arsen’s Invigoration lvl 10

You guys have any advise on what should i swap out for the Roiling Consequence or if i should even do it? As just a Battle Pass buyer i wont realistically be able to go over lvl3.

Thank you.