I have the Mustang Micro. It won’t work with a looper since there would be no way to play the loop back from the looper into the micro. there is one input for your guitar signal and you can listen to backing track via bluetooth at the same time. The best use is to play along with a lesson playing on a computer/tablet via bluetooth and using a wired headset to monitor(does not support a bluetooth headset), It is a good headset amp with a dozen amp models. It is portable so iyou can practice anywhere/anytime you want without dsiturbing your family. decent battery life. you can play for several hours before recharging. you can’t use it with a looper.
not sure what you budget is but the best solution for a looper would be an amp with an effects loop with the effects loop you can have one sound for your rythym and a different sound for you lead.
You can use a looper on an amp without an effects loop but the rythym and lead parts will have the same sound. You can find a bunch of info on the net about effect loops.
Yes, you can use the micro with a looper. Connect your guitar to the looper input with a guitar cable. Plug the Fender micro into the looper output. Connect your headphones to the micro.
The things to consider are:
You are recording the dry signal from your guitar into the looper. Any effect you apply with the micro will affect the whole loop. As PC429 pointed out, you can’t record a clean rhythm and then overdub with a distorted lead tone.
Every time you want to adjust the fender micro you will need to lean over to the pedal which is probably going to be on the floor.
You might need an extension cable for your headphones. e.g.
IMO you would be better with a floor multifx unit. There are many models which are compact, and portable (Boss GT-1, Zoom G1X Four, etc.) and you can plug your headphones into those and use them. Most of these also come with a built-in looper, so that’s one less thing to worry about.
IMO, having external pedals and all of the cables (and, potentially, power supplies if you don’t want to run off batteries) negates the benefits of a plug-in headphone amp like the Mustang Micro.