I would love to see a tool or a command that would help to transform notes which cross the "imaginary barline", like so:
Assuming 4/4, Bar 1 violates the imaginary barline, Bar 2 is corrected for it. This convention is commonly used and the logic of it seems doable to implement. You could select multiple bars, invoke a command and any notes overlapping the boundary between beats 2 & 3 would be split and tied.
Real-world example: This...
would become this: