how to add if condition for mouseover (cursor) exceeds three scond in a "a tag"?

My question is not a time duration of animation. My question is - If mouse is stay more than 3 second in TAG. Hover effect will come, but never load the data before 3 second. So load the data after 3 seonds only. From my end below are my html code and i can't add class name and id name because all are dynamic

Html:

 <a href="#" style="display: inline !important; cursor:pointer;">
   <div onmouseover="Snapshot("some backend data")"></div>
</a>

This type of structure i am looking.

if (time >= 3000s)
{
add data
}
else
{
add another
}

You want to create a function for the mouseover event that starts a timer. If that timer reaches 3000ms, or more, then call the function to update whatever it is you are updating.

Also create a mouseout event that clears the timeout.

<a href="#" onmouseover="snapshot('some backend data')" onmouseout="clearSnapshotTimeout()">Move your cursor and wait 3 seconds</a>

var snapshotTimeout;

// code that deals with (loads) data here.
function snapshot(data) {
    snapshotTimeout = window.setTimeout(function() {
        alert('alert happens after 3 seconds');
    }, 3000);
}

function clearSnapshotTimeout() {
    window.clearTimeout(snapshotTimeout);
}

EDIT:
If you cannot add a mouseout event to the html pages then you could try this:

<a href="#" onmouseover="snapshot('some backend data')">Move your cursor and wait 3 seconds</a>

var snapshotTimeout;
// code that deals with (loads) data here.
function snapshot(data) {
    snapshotTimeout = window.setTimeout(function() {
        alert('alert happens after 3 seconds');
    }, 3000);
}

function clearSnapshotTimeout() {
    window.clearTimeout(snapshotTimeout);
}

// add the mouseout event handler to each element that has a mouseover attribute.
var mouseOverElements = document.querySelectorAll('[onmouseover^="snapshot("');

for(var i=0;i<mouseOverElements.length;i++) {
  console.log(mouseOverElements[i]);
    mouseOverElements[i].onmouseout = function() {
        clearSnapshotTimeout();
    }
}