The question is about God's punishment on nations that violate his covenant with Abraham and his descendants. That includes the descendants of Isaac, but nations other than Israel were also descendants of Abraham and were also required to be physically circumcised.
Point One is that physical circumcision was no longer required for the people who would be brought into the New Covenant of faith once Jesus inaugurated that. The New Testament is perfectly clear about that, also that Jews and Gentile are equally enabled by God to enter into this relationship with him via the New Covenant.
Any modern-day application of that particular part of Jeremiah's prophecy will have nothing to do with physical circumcision.
Point Two relates to the punishment God brought upon Israel and those other nations. History shows the initial fulfilment - literal war, death and destruction, with God prompting and using nations like Egypt and Babylon to execute this judgment. Only yesterday I was reading Jeremiah chapter 47, with specific mention of these locations drawing me up short, to wonder about what's going on right now. Some details state:
"The word of the Lord that came to Jeremiah the prophet against the
Philistines, before Pharaoh smote Gaza.... Behold, waters rise up out
of the north, and shall be an overflowing flood, and shall overflow
the land, and all that is therein; the city, and them that dwell
therein: then the men shall cry, and all the inhabitants of the land
shall howl... the fathers shall not look back to their children for
feebleness of hands; because of the day that cometh to spoil all the
Philistines, and to cut off from Tyre and Sidon every helper that
remaineth; for the Lord will spoil the Philistines... Baldness is come
upon Gaza; Ashkelon is cut off with the remnant of the valley: how
long wilt thou cut thyself?" Jeremiah chapter 47, A.V.
The initial fulfilment happened around two and a half thousand years ago. But is there any basis for thinking God's punishment will have a second fulfilment now? The passage used by the OP requires other statements written by Jeremiah at that time, such as the one I have pointed to, to obtain the whole picture. There are others regarding Moab, Egypt, Ammon, Edom, Damascus, Elam and Babylon.
But Point Two requires the same understanding as does future application for Point One: the literal initial application becomes symbolic, spiritual application in the future. Spiritual principles need to be worked out, and then an understanding for today may become clear.
One principle is the centuries of hatred against Israel that many nations have to this day. Chapter 48 lists various principles that will incur God's judgment: "because thou hast trusted in thy works and in thy treasures, thou shalt also be taken (v.7); Cursed be he that doeth the work of the Lord deceitfully (v.10); Make him drunken: for he magnified himself against the Lord: Moab also shall wallow in his vomit, and he also shall be in derision. For was not Israel a derision unto thee? (vss.26-27); Moab is exceeding proud, his loftiness, and his arrogancy, and his pride, and the haughtiness of his heart.(v.29) Moab shall be destroyed from being a people, because he hath magnified himself against the Lord. (v.42) I will bring the calamity of Esau upon him, the time that I will visit him." (ch.49 v.8)
Any application today should surely be for all the nations to examine themselves in light of God's historic dealings with those nations, to see if they are guilty of the same things that are so abhorrent to God. It is for all who are in the New Covenant today to see if they are guilty of the same things that brought God's judgment on those in the Old Covenant. This is because other prophecies speak of a future judgment coming on the whole earth, at Christ's second coming. How do all the nations, and all those claiming to be in covenant relationship with God today measure up? Will they stand, or will they fall at his visitation, accompanied by the outpouring of judgments from heaven as foretold in Revelation?