Sebbe,
That was great. You can keep making your recordings using this approach, it sounded good and we could see you playing. So all boxes ticked.
And a couple of folk said, that place to post such recordings is
here as a new topic.
My 2cs on "stiff" and "lacks some passion". I'm not sure as I write this how long you have been playing, your learning history, which will be a factor in playing with feel and expressing emotion.
I think initially it is about laying a good foundation ... steady, consistent, and rhythmic strumming, clean chords, smooth changes keeping to tempo and the beat. To achieve that is something to be proud of, to celebrate, and based on the video you are doing well.
Justin talks a lot about making it feel good. I think some of this comes through dynamics, being able to vary the weight of the strumming to create accents. It involves targeting strings, being able to mix up when you are strumming the thicker strings vs thinner strings vs all the strings. More advanced righthand techniques like lightly muting thick strings to change the tone, the percussive hit.
I think with these additions one can be more expressive. And I think then it goes even further in that while one is strumming in time, there's a way of making it sound natural, fluent vs having a more mechanical feel. And I don't know if that is something one can be specific about or if as you play more you just become more relaxed, more into just playing vs concentrating on technically playing without losing beat, fluffing chords.
Those are my musings, from a player who is still a relative beginner and very much exploring this topic myself.
But as I said, looks and sounds like you are doing well, just keep on keeping on, enjoy it and you will continue to improve.