Yes it will : check if the powerbank can charge a macbook 2016 and have a type C port (no adaptater needed) then it should charge the cube mix plus.
a cheaper alternative here : https://www.amazon.com/16750mAh-Portable-Charger-Nintendo-External/dp/B01KHDFXCE/ref=sr_1_cc_4?s=aps&ie=UTF8&qid=1499176290&sr=1-4-catcorr&keywords=imuto+type+c
Can anyone confirm the anker PowerCore+ Power Bank works or did try any other? I just bought the RAVPower 26800mAh but unfortunately it is not charging. My Inateck 45W USB C charger works perfectly, so the cable should be fine.