A:Answer It doesn't matter which way you connect them together. Regardless you'll want to connect your soundbar to the tv visa eARC for sound.
For video you can connect the 4k player to the tv or use the soundbar inputs. The latter forces you to use 3 remotes, the tv for power, the soundbar remote for volume and input and the 4k bluray player remote to control the movies.
Likely, if your tv has cec control, it will control your soundbar power and volume, eliminated the need for your soundbar remote if you connect your bluray player to your tv.