Awkward venting for OTR microwave. Can I do it?

[Rainedoc]

I just finished a mostly DIY kitchen reno. The new stove had to move over a few inches to meet new code, but that meant that the vent from the old hood fan is now not lined up with the new OTR microwave. I have attached a picture in the hopes that some mustachian can help me out with venting solutions. We cannot move the vent any further to the left because of a stud. There is also not as much distance between the top of the microwave and the current vent as the install instructions say there should be (only about 4.5"). Should I call a pro or is there a way to custom fashion a venting solution? Thanks!

[Greg]

Your pic appears to be upside-down, but I think I see what you want to do.  You need a boot adapter to go from the rectangular opening to 4" or whatever size the round is, and then an adjustable elbow to the pipe from the wall.  You may have to cheat and custom adapt your boot to the round in a more creative way, but it can be done with stock parts, tin snips, sheet metal screws and aluminum tape.