I don’t believe it is possible (at least not without custom-coding something like that), but it would be invaluable. I want to do the same thing. This would provide a degree of flexibility without letting the page design turn into a free-for-all.
A workaround (and not a great one) is that you can embed an Elementor template shortcode in the WYSIWYG editor area. For occasional use this would perhaps be OK. If you need to use Elementor on tons of pages, this is untenable, though.
I don’t believe it is possible, but it would be invaluable. I want to do the same thing. This would provide a degree of flexibility without letting the page design turn into a free-for-all.