Source to target mapping diagram

This may sound like a simple request but I have been trying to find a decent modelling tool that can design a STM (source to target) mapping diagram. There are many tools in production applications for implementation of STM but nothing that I can find for documentation to give to the ETL developers.

This will be a very nice value add
I would also like this

This feature is also required in my work.

And for me also

Me also and a lot of value for DWH projects