shared tooltip
I want to get something like this

Where I have shared cursor. And want show in tooltip info from all uplot graphs. And if is it possible at the bottom show uplot graph only with time scale with shared cursor.
certainly do-able with some work. might be more straightforward to manually call .setCursor() on all plots rather than using the built-in cursor sync, but would need some exploration and would depend on requirements for live selection sync, etc.
how far have you gotten?
Now I do only research. Grafana has shared tooltip.

But each chart has own tooltip. Maybe it is good. As I understand we can do that in uPlot?
yes, but you'll have to write a bit of code.
We can use the following code to achieve the tooltip sync between charts cursor: { sync: { key: "sync" } }