Hi, can I create modules in polybar with similar functionality? (hovering which shows some text and add nice underline and also drop down menu, for example pavucontrol for pulseaudio)
I'm honestly not 100% sure, but I don't think so. Waybar does though, with the tooltip option.
Waybar is similar to Polybar, but only works on Wayland rather than X11. Configuration is a bit different, but similar in many respects. If you're using i3 with Polybar now, you can install Sway as the window manager and drop your i3 config into ~/.config/sway/, it should work exactly the same as i3 after a few minor tweaks. Once Sway is set up, you can install and configure Waybar. The config file is not a drop-in replacement like Sway was for i3, but if you can figure out Polybar, you can figure out Waybar.
Sadly no.
(You can prolly create drop down menu in a hacky way by creating some script that would launch a drop down looking menu and have your wm's window rules display it under the module when clicked)
Btw waybar supports tooltips(hover text thingy) but its wayland only