Sometimes I go to CARM which also argues against transubstantiation here:
carm.org/transubstantiation
Of course, there’s Justin Martyr…
Now it is evident, that in this prophecy [allusion is made] to the bread which our Christ gave us to eat,
in remembrance of His being made flesh for the sake of His believers, for whom also He suffered; and to the cup which He gave us to drink,
in remembrance of His own blood, with giving of thanks. (Dialogue with Trypho, 70)
There’s always Clement of Alexandria…
The Scripture, accordingly, has named wine
the symbol of the sacred blood (The Paedagogus 2.2)
And Origen…
We have a
symbol of gratitude to God in the bread which we call the Eucharist” (Against Celsus, 8.57).
Eusebius of Caesarea…
For with the wine which was indeed the symbol of His blood, He cleanses them that are baptized into His death, and believe on His blood, of their old sins, washing them away and purifying their old garments and vesture, so that they, ransomed by the precious blood of the divine spiritual grapes, and with the wine from this vine, “put off the old man with his deeds, and put on the new man which is renewed into knowledge in the image of Him that created him.” . . . He gave to His disciples, when He said, “Take, drink; this is my blood that is shed for you for the remission of sins: this do in remembrance of me.” And, “His teeth are white as milk,” show the brightness and purity of the sacramental food. For again,
He gave Himself the symbols of His divine dispensation to His disciples, when He bade them make the likeness of His own Body. For since He no more was to take pleasure in bloody sacrifices, or those ordained by Moses in the slaughter of animals of various kinds, and was
to give them bread to use as the symbol of His Body, He taught the purity and brightness of such food by saying, “And his teeth are white as milk” (Demonstratia Evangelica, 8.1.76–80).