DD is frightened by a lot of fiction on telly, in films, in books, so she really likes factual content. What she loves is kids reality stuff on youtube, e.g. kids acting out a playmobil game or a game with dolls, parents doing fun set ups with kids, somebody showing crafting tips. I don't see a problem with this so long as we limit it (we do) and use it strategically (as a reward, or for when she needs a little downtime). She's not allowed unboxing videos/advertorials and she's fine about that.
However, she doesn't watch any in British accents. I can see how it's affecting her speech and her play. There's one Australian thing where the kids put on fake baby accents and she copies that and it's extremely annoying. However, mostly she's watching things in American accents and it's all she copies, mostly in voices that American friends would roll their eyes about.
I'm cringing a bit because there isn't anything really wrong about this, she's trying different things, being imaginative and acting, essentially. My main complaint is that even with the volume down DH and I find the stuff she's watching really grating. Also, some of the things she's saying sound really odd to British ears. I'm not even sure that finding the same stuff in British accents is going to help, it's probably the style of what she likes which is annoying, but I'd like to give it a try.
I would really like some suggestions for British options to add to the mix, but a quick google search on British youtube for kids brings up nothing but things to teach you english (mostly in US accents). Has anyone got anything they can recommend?