Angular 13 Routing: How to loadChildren with canActivate in named outlets

Question

What I want

I want that the preview is loaded in the left outlet, depending on stuff that is defined in the foo.guard. If it is not loaded a fallback module should be loaded into the left outlet. The edit form sould always be loaded into the right outlet.

My question:

Is it possible in angular 13 to lazyload two module in one named outlet, where canLoad/canActivate decides which of the two modules should be loaded?

What I have:

    {
          path: 'customer/:customerId',
          component: VerticalSplitscreenTemplate,
          children: [
            {
              path: '',
              loadChildren: () => import('../modules/preview/preview.module').then(m => m.PreviewModule),
              outlet: 'left',
              canActivateChild: [FooGuard],
            },
            {
              path: '',
              loadChildren: () => import('../modules/fallback/fallback.module').then(m => m.FallbackModule),
              outlet: 'left',
            },
            {
              path: '',
              loadChildren: () => import('../modules/edit-form/edit-form.module').then(m => m.EditFormModule),
              outlet: 'right',
            },
          ],
    },

What actually happens

If the guard returns false, I'm gonna redirected to "/", without the fallback module loaded. If the guard returns true, the form and the preview is loaded as expected. So the fallback setting seems to be totally ignored.