GRANT UNSAFE ASSEMBLY TO sa

select p.permission_name from sys.fn_my_permissions(null, 'server') as p

SELECT HAS_PERMS_BY_NAME('sa', 'LOGIN', 'UNSAFE ASSEMBLY')

SELECT pr.name, pe.permission_name 
	FROM sys.server_principals pr
		INNER JOIN sys.server_permissions pe
		ON pr.principal_id = pe.grantee_principal_id
	WHERE pr.name = 'sa'

execute as login = 'sa'
SELECT HAS_PERMS_BY_NAME(null, null, 'UNSAFE ASSEMBLY');  
revert

select p.permission_name from sys.fn_my_permissions(null, 'server') as p