If you want the room to look like these I'd start with the floors and walls. Darken the floors a bit and go with the white color you seem to like in examples. You could even paint beams on the ceiling white and maybe add a nice mantle and see if that helps? Tearing apart the fireplace looks like a big undertaking!

IMO the fireplace should go honestly we had a fireplace in one bedroom and I think we used it 3 times that one just has no connection to what you are wanting and all the paint and stain in the world will not make it work The rooms you like are light and airy nothing light and airy about that. Maybe if you really want one get a very flat contemporary fireplace

the positioning of the fireplace makes it difficult to enjoy.... the way the current owners have the bedroom set up, only sitting on the foot of the bed facing sideways leads to enjoyment.

so, if you want a fireplace at all in the bedroom, post a floorplan (or wait til you move in if you cannot accomplish that now) to see if the furniture can be arranged so that the fireplace can be enjoyed. then work on how to redo the fireplace to one you like.

but there is not a lot of point to redo a poorly situated fireplace in a bedroom. it will still be poorly situated.