What you can do
- Preview each network as you type, with the cut point where its limit ends the text.
- Override the text for one account while the rest keep the original.
- Split text into parts for a thread at each network's own limit.
- Add a first comment, with a delay, on networks that allow one.
- Save the selection of accounts and settings as a set to reuse.
The composer uses the same rules as the free character counter and post previewer, so a post that passes there is not refused for length when it is sent.