Once upon a time I used ToDoist and Trello. Trello is the best kanban offering you will find in my view. However, I don't use Trello anymore as the basic kanban function is now available in other apps (e.g. ToDoist). Although it's not as good as Trello it works well enough for me.

I did have an automation set up where by if marked a trello card somehow, it would create a task in ToDoist. It might have been a native Trello power up but I cannot exactly remember.