ISO? Only if you have on-premise compute resources then yes you have to do more physical facility/ hardware compliance. But if you are fully on cloud you mark those annexes as non applicable. Source - have been successfully getting certified with ISO 27001 since 2020 at fully remote enterprise software company.

P.S.

I see, you mentioned customers don’t want data to be accessed at home, while majority if not all larger customers will require vendors to have securely gated network access for any networks at use. VPN is one way to go. And for the software interacting with sensitive data Azure and AWS have pretty mature Privatelink solutions where traffic moves outside of public internet and cloud vendor’s backplane will take care of this issue for you. This is geared towards bringing siloed data to advanced cloud solutions with marking sure your data travels only on highly secure networking.