this. "it doesnt work" doesn't help you or the users willing to help you. nvidia to amd offload does work with the correct configuration. you get out what you put in.
since you didnt post the requested outputs, nobody other than yourself knows whats going on.
replace whatever gpu configuration (if any) in /etc/X11/xorg.conf.d/
(probably 90-mhwd.conf) with this one.
#/etc/X11/xorg.conf.d/offload.conf
Section "ServerLayout"
Identifier "layout"
Option "AllowNVIDIAGPUScreens"
Screen 0 "iGPU"
EndSection
Section "Device"
Identifier "iGPU"
Driver "amdgpu"
Option "DRI" "3"
EndSection
Section "DRI"
Group "video"
Mode 0666
EndSection
Section "Extensions"
Option "Composite" "Enable"
Option "RENDER" "Enable"
EndSection
Section "Screen"
Identifier "iGPU"
Device "iGPU"
EndSection
Section "Device"
Identifier "nvidia"
Driver "nvidia"
EndSection
save/exit/reboot
do keep in mind, both nvidia and amdgpu need to be installed. when you installed video-nvidia-435xx it created conf files that are probably conflicting with what you want to do. so in case i forgot to mention it... post the requested outputs