Use of HA Web components in custom UI

[kvj]

Hi,

I'm working on the UI for my custom component, following https://developers.home-assistant.io/docs/frontend/custom-ui/creating-custom-panels

Can I use existing ha-* web components for my UI? I would like to, they're super convenient, but the documentation isn't very clear about it. Here https://developers.home-assistant.io/docs/frontend/custom-ui/lovelace-custom-card example shows how to use ha-card, but, when I'm trying to use for ex. hass-tabs-subpage-data-table, it doesn't work, because of the lazy loading. But after I visit any built-in panel which is using that component, my panel is also being loaded. I understand all webpack, modules, import stuff, and that I can't import ha-* components directly into my custom JS.

Why am I facing this?
I originally started making my UI using the tutorial above, importing lit and custom UI web components, and I've realized that I can't import @paper, @mwc web components, as they're already registered inside the page. So, I either would like to find a way to re-use HA stuff as much as possible (preferred) or will be forced to use some completely different UI library to avoid customElements conflicts.

Is it possible (recommended) to re-use HA web components for the custom UI?