Does "he chose us in him before the foundation of the world" signify the chronological sequences in God's plans within eternity?

Not chronological sequences but perhaps, logical sequences might be acceptable.

Remember we are speaking of before the foundation of the world or before creation time begins.

The logical sequences not chronological, will be like this :

First : One Holy, Almighty God existing in eternity with infinite majesty and glory.

Second : One Holy God sees Himself a King, and a visible image was seen, the Logos incarnate, in the person of Jesus.

Third : Then God, sees a vision of a Heavenly Kingdom ruled by a glorified Jesus, the King of Kings and the Lords of lords.

Fourth : If God wanted to fulfill the vision of being King, a glorified Queen is needed. And ofcourse, a King must be born from the Queen.

**Fifth :**If glorified Jesus is a King, there must be a glorified Queen, and a Heavenly Kingdom ruled by a King in the presence of a Queen needs people to rule, and so, the creation of mankind were also part of the wisdom of God.

Sixth : And, God seeing a vision of Himself being born, had to create a masterpiece, a creature, a chosen Woman with an immaculate heart for Him to dwell. -Proverbs9:1 and Sirach chapter 24

Jesus existing in the bosom of the Father, and the chosen woman existing in the heart of God in eternity.

**Seven :**And so, in order for this Heavenly Kingdom, be ruled by Jesus the King of Kings and Mary the Queen, a "Wisdom must be qanah" that will encompass the Divine Plan of God, in starting a creation and how it will end. -Proverbs8:22

Back to your question.

Does "he chose us in him before the foundation of the world" signify the chronological sequences in God's plans within eternity?

In the order of logical sequence, the vision of God seeing Jesus as His visible image is the first, and a chosen Woman to be His Mother is the next, and the creation of mankind is the third.

After the Wisdom had been qanah or birthed, then, the Omniscient God now have a companion, an "Artisan", in starting the creation.

The question is, what moved God in eternity, existing in His infinite majesty and glory to create the "Beginning, the Heaven and the Earth"?

Bl.Ab.Fulton Sheen said, "Love begins with a dream."

God created everything out of love, and since love begins with a dream, we need to somehow seek God's wisdom, to understand what moved Him to create or what is God's dream.

The God of Love desires to be love by a chosen creature, a Woman.

Mary is God's dream in eternity, and God created a masterpiece, an immaculate heart that can love Him in His Most Holy Trinity.

Mary became the beloved daughter of the Abba Father. beloved Mother of the Begotten Son, and beloved Spouse of the Holy Spirit.

Mary is the beloved of God, and the reason why God created the beginning, heavens and the earth, to fulfill God's dream to be loved.

It's no wonder, the greatest commandment of God is to love Him with all our hearts, minds, strength and soul. Only the Blessed Virgin Mary the chosen Woman had fulfilled this greatest commandment perfectly and completely in the Most Holy Trinity.

Ave!

The chronological aspect of that verse could be linked to the words, 'chose' and 'before' [the foundation of the world].

A certain One decided to choose certain ones. That implies thought, and some kind of time-aspect in which to arrive at a decision as to the choice to be made.

However, we are then told that the decision was made before a certain event. That particular event is called "the foundation of the world (i.e. kosmos). This implies the founding of a kosmos. It speaks of the basis upon which a particular kosmos came into existence.

Therefore, before this kosmos existed, God took a decision to choose certain people ("us" says the apostle, but he does not say all people) who were yet to be created / born. After all, no person could exist in a kosmos prior to that kosmos existing. The choosing is only inclusive of the persons in consideration. It is not about excluding anyone - it is only an inclusive choice.

In the realms of timelessness (or, the realms of that which is other than time), in that other dimension that God created for his own habitation, where eternity obtains, God planned, or purposed things for certain people on a future kosmos . This universe requires time in order to exist, for it takes time for light to travel, for sound to travel, for growth, for decay etc. The time element integral to our universe is all we know, for that is all we can experience. None of us have experienced eternity. This means we just cannot explain that first part of God's planning and purposing. We can only get the measure of time within our universe once that universe exists, and we exist. And, before we can exist, our kosmos must exist.

We know from God's written communication with humanity that eternity is spoken of again, when those chosen ones will die physically, step out of time, and enter eternity. So there may be a sort of sequence of events, from our point of view, which is that of earth-bound-time. Yet until we experience eternity, we cannot presume to know how events 'work' in the dimension of eternity, that God inhabits.

This very good question might have to wait until the OP experiences eternity before getting the answer!