Because power is a factor, the Huawei should not be on your list.
Between the Xiaomi Redmi 4X and Nokia 6, I would go for the Nokia 6. As much as the battery is smaller, it offers the best in aesthetics, software experience and that battery is good enough to last the whole day.
If you really prefer having two-day battery life, then the Xiaomi is the device for you.
Since I learnt that warranty is an important factor in the Kenyan market, buying a Nokia 6 from Safaricom would be the better option - no pun.