None of those passages talk about weakness as sin, but it is about suffering and the general vanity of the mortal life. See Ecclesiastes 2 on vanity. Paul talks about the predestination language- the creation was subjected to vanity, not by itself but by God who suffered/allowed (not intended) it, in hope of redemption from the corruption and vanity to glory.
David Stern commentary:
19–25 Our inheritance involves an ecologically ruined world that will one day be restored (Ac 3:21, 1C 15:23–28, MJ 2:8–11, Rv 21:1). It was made subject to frustration because of human sin (Genesis 3:16–19)—the intractability of the physical world is not merely a natural law, and one day it will end (for an imaginative fictional portrayal of such a phenomenon see the final two chapters of C. S. Lewis’s The Last Battle, in his series, “The Chronicles of Narnia”). Of this we have a certain hope, for which we are waiting eagerly, but with patience. This is the larger context of whatever suffering, discouragement and doubt we experience—a context of hope.
In 2 Corin. 12:9, Paul talks about the suffering, and it can be applied to all general situations of frailty, anxiety, troubles, hardship we find ourselves. The power of God will be manifested the most when we are in the lowest. It is not about sin, which grieves God, from which he came to save us from by his sacrifice, to implore us to repent from sins and be reconciled to God. Sin grieves God, and repentance makes him rejoice. See Ezekiel 33, Luke 12.
[Isaiah 40:29-31 ESV]
29He gives power to the faint, and to him who has no might he increases strength. 30Even youths shall faint and be weary, and young men shall fall exhausted; 31but they who wait for the LORD shall renew their strength; they shall mount up with wings like eagles; they shall run and not be weary; they shall walk and not faint.
[2Cor 5:18-21 NHEB]
18But all things are of God, who reconciled us to himself through Jesus Christ, and gave to us the ministry of reconciliation; 19namely, that God was in Christ reconciling the world to himself, not counting their trespasses against them, and having committed to us the word of reconciliation. 20We are therefore ambassadors on behalf of Christ, as though God were making his appeal through us. We implore you on behalf of Christ, be reconciled to God. 21For him who knew no sin he made to be sin on our behalf; so that in him we might become the righteousness of God.
[2Cor 12:20-21 NASB]
20For I am afraid that perhaps when I come I may find you to be not what I wish and may be found by you to be not what you wish; that perhaps [there will be] strife, jealousy, angry tempers, disputes, slanders, gossip, arrogance, disturbances; 21I am afraid that when I come again my God may humiliate me before you, and I may mourn over many of those who have sinned in the past and not repented of the impurity, immorality and sensuality which they have practiced.