Mobile: Remap quick switcher button on the mobile navigation bar

You can get the ⊕ button’s element by running

const actions = app?.mobileNavbar?.containerEl?.querySelectorAll('.mobile-navbar-action');
const plusbutton = Array.from(actions).find(action =>
  action.querySelector('span.clickable-icon > svg.lucide-plus-circle')
);

That’ll save the ⊕ button’s element as plusbutton. You can confirm this by running

plusbutton.click();

From there, you can do something similar to what I did with the reading mode toggle button.
[Mobile] Make the reading mode toggle button more reachable (overrides the ribbon menu button) - Share & showcase - Obsidian Forum