Belkin RT3200/Linksys E8450 WiFi AX discussion

Thanks, i'm not yet sure if i should proceed with testing. As a replacement i have an old raspberry with openwrt, but without wlan.
My main goal is to test if it helps for my problem Pppoe can't connect unitl i stop it!? (but its unlikely).
... I think i should not change the e8450 but configure the rpi for testing