qBittorrent official forums

is that possible not to include stalled torrents into the download count, if I have one?

for example, I've set a limit of 3 simultaneous downloads, and one of them stuck.
then we have a bottleneck, when only 2 downloads could be active, thus leaving a lot of unused bandwidth

or, for example, if a download remains stalled for 5 minutes, and there're queued downloads, simply push it back to the end of queue.

While I don't understand the whole system of limits, i.e not being only applied to really working torrents, forced ones also being counted...
I suppose you can follow the advice from this link:

https://github.com/qbittorrent/qBittorrent/issues/5276
Putting max. active torrents to -1 and then ticking the "Do not count slow torrents..." option.

That should work. Stalled ones should not be considered and you will have 3 working downloads.
Try it and report if it works!