It's done!
Code like this 🙂
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declare @before int, @after int, @oSheet1 int, @oSheet2 int
EXEC @retcode=sp_OAGetProperty @ExcelObj, 'Sheets.Item("sheet1")', @oSheet1 OUTPUT
EXEC @retcode=sp_OAGetProperty @ExcelObj, 'Sheets.Item("sheet2")', @oSheet2 OUTPUT
set @Method='Copy'
exec @retcode=sp_OAMethod @oSheet2, @Method, null, @before=null,@after=@oSheet1
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