There has been a resurgence of sorts among Roman scholars of interest in late antiquity, but a lot of books about the 4th and 5th centuries are decades old. This doesn't necessarily mean that they aren't worth reading, as it is important to understand the historiography of the topic as well, but many of them are outdated in some ways. For instance, some historians now argue that the Roman Empire never really fell in 476, but rather it continued to live on through the various Roman traditions and laws (and other things) that survived into medieval Europe and beyond. That being said here are a few books that I think are really good sources for the period in question.

There’s Guy Halsall’s Barbarian Migrations and the Roman West, 376 - 568 which is an excellent book that focuses on Roman interactions with non-Roman peoples throughout late antiquity.

Patricia Southern’s The Late Roman Army which, as the title implies, focuses on the Roman army during the late Empire. As well as her The Roman Army which is much more recent and isn’t as specific as the other book, because it focuses on all of Roman history, but still has a very good section on the late Roman army.

Peter Heathers Goths and Romans: 332-489, The Goths, The Fall of the Roman Empire: A New History Of Rome and the Barbarians, and Empires and Barbarians (I own the last two but haven’t really read them much, but I generally find Heather to be a solid historian) There are some criticisms by other historians, like Halsall, of Heather’s work that I somewhat agree with but I still his books on the Goths are at worst a decent study of that period. The main point on which I disagree with Heather is that he argues the migrations or late antiquity were an invasion whereas historians like Halsall, and to some degree myself, argue that the numerous migrating barbarians were largely peacefully absorbed with some instances of conflict.

Michael Kulikowski also has several great books that focus on late antiquity, especially non-Roman peoples of that era. I haven’t actually read any of his, but I haven’t come across anything that implies they aren’t good. Kulikowski belongs to the same school or thought as Halsall and generally argues against the ideas of historians like Peter Heather. But I think it’s important to at least read a few things from both schools to understand the argument that each is making and then form your own conclusions.

The "founder", if you will, of this school of thought is Walter Goffart. Goffart at times can come off as...rather militant with some of his views, especially his view that the whole idea of Germanic people existing in antiquity stems from Nazi ideology, and he is often criticized by historians like Bryan Ward-Perkins who argue that the Roman Empire did collapse and that Germanic peoples had soome kind of shared cored culture (its more complex than that of course). But he is a good historian A lot of Goffart's work is in German but I believe most of it has been translated, his Barbarian Tides is one I think it is pretty good and its from 2006 so its not too old either.

On the other side of the coin are historians like Herwig Wolfram and Walter Pohl, who are leading scholars of the Vienna School of history (which included Peter Heather). Pohl is more fluid in his approach and does agree that Germanic people didn't really have any kind of shared culture or identity but doesn't go as far as historians like Goffart. Wolfram is a much more staunch believer in the idea that these peoples did have a shared culture. But nevertheless they have both written several works on Roman history. I can't think of the names of their books of the top of my head but I know some of Wolfram's work and, I believe, most of Pohl's books have been translated from German to English. If you give me a couple of hours I can probably find the actual books, I know I own a couple there just packed up in boxes.

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I hope this was helpful, and I apologize if it seems kinds of disjointed haha, I'm trying to eat lunch and type this at the same time (food waits for no man) and part of it is from a previous answer I gave to a similar question, Feel free to ask any follow up questions though and I'll do my best to clear things up if need be.