2 wordpress (1 main / 1 sub-domain) on the same dashboard possible?

Hi all,

I have a wordpress on my domain with WPML, WooCommerce and some other plugins.
I would like to create a subdomain B2B.domaine.com with a second wordpress/wooCommerce, a separate one I think because even if there is the same products, they will have different prices and options, so this one will be on the sub domain. On this one, no need of blog page etc … I would like also this subdomain will be private (login/password I will provide for users)
But What I would like is to manage both website on the same admin space… Like that, they could have the same theme, some shared plugins etc …
I looked on the multi site system but i’m not sure it’s what I want because the subdomain will be virtual if i understood.

What is for you the best way to do for this config?

Thanks in advance