Information on licensing for DR Site

Grateful if someone can help me. I have a production site under VMware ESX consisting of 13 VMs running SLES 15 SP1 as guest O/S. I need to have a DR Site that will host 2 of the 13 SLES VMs and I wanted to know if i need to cater for licenses/subscriptions for these 2 VMs. To be noted that these 2 VMs will be passive and will be start manually if the production site fails.
Thank you.

Seems like if they are basically clones of one another that a second license would not be needed. Especially if only one was running at a time.