Multi select records in sub grid CRM 2016

Hi team,

I know that since 2013 we cannot select multiple records from sub grid and we need to switch to associated view to do that. However, our client wants to select multiple records from same page itself. Is there a workaround? Like HTML webresource/IFRAME? where in I can display records and user can select multiple records from same page without switching to Associated view page?

Thanks in advance!