In response to your question, the most closest scheme that the UK authority has is the graduate entrepreneur visa, which can be valid up to 2 years. However the only clause to that visa, is that you need to study in the UK, must complete a degree with a University and will then be able to put forward your idea for the sponsorship. As part of that application, there is a requirement to provide evidences of any previous experience you may have. Given that you do, this would support your application.
The only other route available would be the Tier 1 entrepreneur visa, however, it would be correct that you need to investment. However if you do not have any funds of your own, you can ask the following bodies in the UK, to invest a minimum of £50,000 in your business idea:
a) a UK entrepreneurial seed funding competition endorsed by UK Trade and Investment (UKTI).
b) a UK government department making funds available for the purpose of setting up or expanding a UK business
c) venture capital firm registered with the Financial Conduct Authority (FCA)