which of this html markup is more right

In your first example, the h2 doesn’t describe the content of the li. In scope of this heading is everything following it, until the next heading starts. So in fact, the previous heading would describe the following content, and so on. This problem always arises when using headings without sectioning elements in lists.

In your second example, the h2 probably contains more than it should (two times "mallname"; the one in the title attribute is not considered to be part of the heading content). But what is the actual content here? There is only a heading, which doesn’t seem to make sense.

Your alt content is probably not correct/useful. When it is exactly the same as the corresponding heading, the you should probably use an empty alt value. But it’s likely that the image represents something in addition to the heading: describe this in the alt content.

Duplicating the heading content in the title attribute doesn’t seem to make sense, either. Only use it for additional helpful (but not essential) content.

So you should use something else: sectioning elements. Judging from the screenshot, it might be the case that article is appropriate (if not, use section).

By using a sectioning element like article, the heading doesn’t have to be placed on the top.

<ul>
  <li>
    <article>
      <a href="/brand/mallname">
        <img src="/Images/mallname.png" alt="Mallname offers … and …. It’s ….">
        <h2>mallname</h2>
      </a>
    </article>
  </li>
</ul>

However, use this only when the h2 describes the ìmg! When the image is only an alternative to the heading (or only decoration, and the actual image content isn’t relevant in this context), why use headings at all? In that case you’d have just a list of links:

<ul>
  <li><a href="/brand/mallname"><img src="/Images/mallname.png" alt=""> mallname</a></li>
</ul>