If you actually paid for the quixel assets you can do whatever you want regardless.
They are yours.
There’s a proof of payment.
You can do with as you please in almost all states regardless of what their terms may say.
If you are using quixel for free, then no. You obviously do not own anything. So you do have to abide by whatever the terms are.
All marketplace assets allow you to freely share with your own development team.
Posting them public is a big stretch obviously. Verging on piracy. It could end up getting you sued.
To share quixel assets you can literally just give people the name of the asset used.
And it’s up to them to then add them into the project.