power-consuming
There are two ways of reverse charging, one is OTG switch port reverse charging (wired), one is wireless reverse charging, these two charging methods will be faster than the usual discharge power consumption, but the battery current and temperature are in the normal range, so the battery should be no harm (unofficial view, for reference only)
This will increase the loss of the battery, because the number of times it is charged is also increased.
It will lose power, and the principle of wireless backcharging is to charge other mobile phones by consuming the power of their own phones