<p>I tried researching on this.But currently no one who has a full fledge integration that you want.Basically what i understood is a multi tenant blockchain platform(with some tweaking) will address your purpose(I am not sure whether you would be achieving your 3rd requirement).</p>

<p>Here is a paper which could help you start on your idea.</p>

<p><a href="https://arxiv.org/pdf/1901.11219.pdf" rel="nofollow noreferrer">https://arxiv.org/pdf/1901.11219.pdf</a></p>
How to build the seamless bridge between two blockchain platform?
<blockquote>
  <p>How to build the bridge between two different consensus blockchain platform?</p>
</blockquote>

<p>use case:</p>

<p>1.we need to ensure visibility of the transaction in both platforms to assure its integrity</p>

<ol start="2">
<li><p>When a smart contract is established on one platform, that contract can be referred to, transacted and transferred to the other platform easily and securely</p></li>
<li><p>The bridge should be able to leverage the one platform and other platform depending upon the transaction type and the TPS requirement. If it requires a faster TPS, then one consensus framework or else normal mining framework of another consensus</p></li>
</ol>

<blockquote>
  <p>How to achieve consensus on the multiple decentralized oracles?</p>
</blockquote>