user102288: I know that it's sounds ridiculous, but i need to create an unconfirmed bitcoin transaction that will be unconfirmed for 2+ hours.I came to a conclusion that i need to create a 0 fee transactions but can't find a solution to make it and broadcast. Another variant was to set the min. fee ( 1sat/byte ) , but sometimes it's got confirmed after 5-10 minutes.How can a achieve the desired result ?

user1221: You could broadcast a transaction that depends on a parent transaction that you don't broadcast until 2 hours later. This would ensure that the child transaction cannot make it into a block until the parent has been transmitted.
Technically, this satisfies your requirements. However, orphan transactions do not get stored into the mempool of bitcoin nodes, but instead are stored in a small (usually room for only 100) orphan cache. So there's a very high chance that it won't be known by the network 2 hours later when the parent is broadcast - i.e. the child will need to be broadcast again.

102288: <p>I know that it's sounds ridiculous, but i need to create an unconfirmed bitcoin transaction that will be unconfirmed for 2+ hours.I came to a conclusion that i need to create a 0 fee transactions but can't find a solution to make it and broadcast. Another variant was to set the min. fee ( 1sat/byte ) , but sometimes it's got confirmed after 5-10 minutes.How can a achieve the desired result ?</p>
 1221: <p>You could broadcast a transaction that depends on a parent transaction that you don't broadcast until 2 hours later. This would ensure that the child transaction cannot make it into a block until the parent has been transmitted.</p>
<p>Technically, this satisfies your requirements. However, orphan transactions do not get stored into the mempool of bitcoin nodes, but instead are stored in a small (usually room for only 100) orphan cache. So there's a very high chance that it won't be known by the network 2 hours later when the parent is broadcast - i.e. the child will need to be broadcast again.</p>
