Assessee died

why you want to show stock sold , when whole stock will get tranfer to Transferree

If transferred to legal heir then it will be liable to GST @ 18%

No...

Kindly follow following Steps
1. Apply new GST registration for Legal hier
2. Legal heir has to visit office of the Proper Officer (Jurisdiction Officer) and submit the Death Certificate of the sole proprietor along with the Succession Certificate before the Proper Officer as documentary evidence.

3. while in process of cancellation of GSTn of desease prop. it will ask you reason for cancellation , select "change in Constitution" option , next it will ask for GSTN of transferree , provide the GSTN of legal Hier . ( it will not ask you to give stock detail )
save & submit the form .

Note : 1. For any balance in credit ledger to tranfer it to legal hier account File ITC 02