Guest player Co-op Nintendo Switch

When playing online or offline couch co-op a second ‘Guest’ player cannot be added. When pressing + on the second pad it asks to sign into a Nintendo account only. Previously on MD1 a guest player could be added at this point without another Nintendo account. I have seen guest coop couch players added on other systems but not Nintendo and have seen many others all asking the same. An error shows 2-BC6TA-0020 “something went wrong”. When can this add a guest player be fixed as this is the only way I play with my family on Minecraft Dungeons.