Or is typing out each kanji on the search bar the fastest way?

You haven't specified which SRS you use. Anyhow, I have this in my Anki card template to automatically create Koohii links:

Quote:<a href="http://kanji.koohii.com/study/kanji/{{Heisig number}}">RevTK</a>

This way I can easily open all of the relevant kanji pages in the background and relearn them in my browser afterwards.

I only use this site

Well on this site (RevTK), when you have failed kanji, and go to the top "study" tab,
on the left side bar there is a "restudy" tab which has a "review" button, and just under there is "detailed list" hyperlink, which when you click it gives you the full list.

Or did you mean something else?

[ファブリス]

That is the purpose of the "Restudy" box on the left hand side in the Study page. It shows up to ten cards from the red pile, in frame number order. The idea being that you might want to work on these in frame number order due to the "building blocks" nature of Heisig's method.

Another way to do it is to click the Detailed List link there, and then keep that tab open by shift clicking or middle click the links to open the Study pages (on mobile, tap and hold and select "open in new tab"). So you can pick and chose from the list. You could sort on Last Review also if you want to restudy the last failed cards ignoring the earlier ones.