Move blocks in ANSYS Workbench
 

I often use the "copy" of a subsystem (block of geometry, block of mesh, ...) and I edit it. But I do not like the way ANSYS places them. Sometime they are placed on the side, sometime they placed are under, sometime they are shifted in diagonal... and this is very annoying, so my simple question: is there a way to change the position of a block in ANSYS Workbench once it is created?

I think you are wanting to move Analysis Systems around a Workbench Project. It is possible to grab and drag them to any area indicated in green. You cannot just put them anywhere you want though.