I use LILYGOTTGO 1,54-inch wrist e-paper.
I try to use some fonts from u8g2_fonts.c, but I don't know how to do this. I added

#include <u8g2_fonts.h>

to the beginning of my source and

display.setFont(u8g2_font_unifont_t_cyrillic);

to the setup, but I get the error

'u8g2_font_unifont_t_cyrillic' was not declared in this scope

I've buyed LILYGOTTGO 1,54-inch wrist e-paper ESP32 (https://aliexpress.ru/item/1005003095240476.html?spm=a2g39.orderlist.0.0.79404aa6XrTWd4).
I try to make a custom autonomous watch with periodical NTP correction via WIFI. Now I do disable WIFI and enable it for correction every 5 minutes, and do light sleep for 15 seconds between time checks.

I have some questions:

1. For 3-5 first display updates the time string is printed weakly, how can I fix it? I use the code from official sample.
2. Which batteries can I use with this module?
3. How can I check the battery charge level and charging status?
4. How can I turn off the red blinking led?
5. Is there any other recommendation for power-save?

Here is my code: https://github.com/zhum/lilygo-epaper-watch