@JJam
Yes you can. Users sometimes purchase an external Roku device in order to upgrade their older RokuTVs which become sluggish or are encountering hardware/OS issues.
Unless you get some performance enhancement from doing the above, no other real reason for doing it though.
Roku Community Streaming Expert
Just another Roku user... I am not a Roku employee.
Insignia RokuTV, Ultra 4660, Premiere+ 3921, Express 4k+ 3941, Streambar 9102