You can already make them via homebrew. Assuming you mean a more streamlined system like the character builder, I believe they have plans to implement that, but there is no ETA.
Due to potential shifts in priorities and resources, development time can change dramatically, so there will never be any sort of ETA given for anything.
The sidekick rules seem a little complicated it would be really cool if you could make one on d&d beyond.
You can already make them via homebrew. Assuming you mean a more streamlined system like the character builder, I believe they have plans to implement that, but there is no ETA.
Due to potential shifts in priorities and resources, development time can change dramatically, so there will never be any sort of ETA given for anything.
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Running the Game by Matt Colville; Introduction: < https://www.youtube.com/watch?v=e-YZvLUXcR8 >
D&D with High School Students by Bill Allen; Season 1 Episode 1: < https://www.youtube.com/watch?v=52NJTUDokyk&t >