None of the SKROSS travel adapters have an integrated voltage converter. For Japan, the manufacturer recommends taking 2 adapters, one 3-pin (for type B sockets) and one 2-pin (for type A sockets, example MUV USB). The PRO adapter above is only designed for 3-pin sockets (in this case type B).

I would say that this device cannot do this, I have one myself and I would be surprised if this device had a transformer in it. Most chargers, such as those for smartphones, are 100-240 volt compatible, so you shouldn't have any problems with them, but I would advise you to check the devices first to see if they are 100-240 volt compatible if you want to take them with you.

Hope I was able to help you