[2020] Guy I need help, my additional assets can finish to download and it's takes a lot of data which result to lag... I don't know what to do... Any suggestions!??

Once you pres play you should see a download bar in the top right of screen. It should finish by the time you get into game. Is this not the case? Can you not press play while the extra download is going?

If your can, please provide feedback in the settings menu and I can DM you for your Epic ID and look up the feedback.

Is it not downloading via WiFi or is that unavailable? Preferably you would download over WiFi, have the extra assets downloaded, and play without issue.

But playing while those assets are downloading would cause some performance issues such as hitching or stuttering.