Here is how to post the same video to Instagram Reels, TikTok, and YouTube Shorts at the same time.
You can also use this tool to schedule videos to post to Reels, TikTok, and Shorts in the future.
Posting to Reels, TikTok, and Shorts all at once
To post to TikTok, Reels, and Shorts at the same time, you can use the social media scheduling tool OneUp.
First step is to connect your Instagram account, TikTok account, and YouTube channel to the Accounts page of OneUp:

Then click “Create a post”, and then select which accounts you want to post to (probably the YouTube, TikTok, and Instagram accounts in this case, but OneUp also supports Facebook, Twitter, LinkedIn, Pinterest, and Google Business Profiles as well):

Then add your video and caption, and add your YouTube Shorts title:

Keep scrolling down and you will find the option to choose the thumbnail (aka cover image) for your Instagram Reel and your YouTube Short (TikTok thumbnails are not supported at this time):

Then either post it to all 3 platforms now, schedule the post for a later date, or save it as a draft:

That is how you post to Instagram Reels, YouTube Shorts, and TikTok all at the same time.
if saved as a draft, will the edited one not be lost?
It will not be lost