Matthew 28:19 is most likely a corruption of the original text. Nobody used that "formula" in the 4 accounts of our Lord, in the book of Acts or anywhere else for that matter.
To be baptized "in" or "into" is to associate the person being baptized with whatever or whoever they are being baptized "in" or "into." Christians are "baptized into one body" which associates them with the body of Christ, and thus Christ himself who is head of his body.
So my answer to your question, "Is there anything in the text of Matthew 28:19 that teaches we should speak a baptismal formula before baptizing someone?" is the text has been corrupted. You can view an entire list of respected scholars and clergymen who take this position here:
[I believe it is ok to link to articles as I have seen dozens of them here on various Stack Exchange posts. If not please let me know and I will delete the link(s).]
Your observations about the obvious disconnect between this verse and the baptisms recorded in the Word are correct.
But if I may explain further, this verse in Matthew 28:19, called "The Great Commission" is taught to be our "marching orders" after Jesus' resurrection. In truth, this commissioning has nothing to do with the body of Christ which was, at that time, still unrevealed and thus unknown (see the "mysteries" in Ephesians 1 and 3). It is actually "The Second Kingdom Commission" which you can read more about in this article:
The article goes into detail but I will summarize its major points here.
Jesus spoke this from up on a mountain. Note his addresses from mountains (referenced in the article) and you will see that when he spoke from a mountain he was speaking about his coming Millennial Kingdom. For example the "Sermon on the Mount" outlines the Kingdom Law that will be in effect during that Kingdom.
"And Jesus came and spoke unto them, saying, All power is given unto me in heaven and in earth." It is not until Jesus returns that this power is given unto him. Currently the "god of this eon" is Satan.
"Go you therefore, and teach [disciple] all nations" -- those risen at the Resurrection of the Just (the former resurrection in Revelation) are to be "priests and kings" unto the nations. Christ will send his own kings (Israeli's) to head the nations during His Millennial Kingdom. The "priests" will baptize and disciple (discipline) the nations according to Kingdom Law.
lo, I am with you always, even unto the end of the world [Greek, "aion," "eon"]. Amen. Jesus is not with us now other than inside us in a spiritual sense. During the Millennial Kingdom he will literally be with them unto the end of that eon (world is not the normal word for world, "kosmos" but is "aion" transliterated into English as "eon" (a period of time with a beginning and an ending). The Millennial Kingdom will end and the New Heaven and Earth will follow. There is no discipleship on the perfected New Earth, only during the Millennial Kingdom.
This commission is to be carried out by those risen from the dead at the start of the Millennial eon; the first fruits of Israel will be used to reach and to discipline the nations during that period of time. It cannot be "to the Christian church" because the church did not yet exist at that point. Further more the Word being preached regards the Kingdom, not the body of Christ and our heavenly, celestial inheritance (Ephesians 1-3).
Matthew 24:40 -- And this gospel of the kingdom shall be preached in all the world for a witness unto all nations; and then shall the end come.
Christians do not preach "the gospel of the kingdom." That is the "Gospel of the Circumcision" Paul speaks about in Galatians, given to the 12; but Paul, "the apostle to the Gentiles" was given the "Gospel of the Uncircumcision." There are two different gospels for two different classes or groups of people. The Gospel of the Circumcision has been held in abeyance until the fulness of the Gentiles comes in (Romans 11:25).
Now one final point is necessary.
Ephesians 4:4-6 -- There is one body, and one Spirit, even as ye are called in one hope of your calling;
5 One Lord, one faith, one baptism,
6 One God and Father of all, who is above all, and through all, and in you all.
There is only "one baptism" in the period of time during which we live. This baptism is into the one body of Christ (associating us with Christ through his church body) and by (the element) Holy Spirit.
Ephesians 1:13,14 -- In whom ye also trusted, after that ye heard the word of truth, the gospel of your salvation: in whom also after that ye believed, ye were sealed with that holy Spirit of promise,
14 Which is the earnest of our inheritance until the redemption of the purchased possession, unto the praise of his glory.
The moment someone believes Jesus died for our sins, was buried, and was raised from the dead (I Corinthians 15:3,4), that person is instantly "sealed with the Holy Spirit" -- nothing can add to that or take away from it. Therefore any fleshly ritual or observance is just that. In other words, there is no water baptism today.
Before Acts there was one baptism: water.
During the Acts period there were two baptisms: water followed by Holy Spirit which was poured "upon" them (they were not "sealed" with Holy Spirit as Christians are today which is a very significant truth)
After Acts, during our administration there is only one baptism: Holy Spirit.
The transition from flesh to spirit occurred during Acts.
Those who persist in the "shadow" of things to come (e.g. water baptism) are falling back into the fleshly worship of the Old Covenant which only symbolized truths that were fulfilled in Christ. We are today baptized with Holy Spirit into the one body of Christ the moment we believe. Let's not put anyone back under the yoke of the physical when God wants us to worship Him "in spirit and in truth" (John 4:24).