Add Text Background
Select the text layer in AE, click "Effects" ->"PAG" ->"Text Background" to add a text background effect to the text layer, which supports modifying the background color and transparency. As shown in the following figure:
Export the PAG file normally.
Preview effect: Open the generated PAG file with PAGViewer to preview the effect of the text background.
Note: The effect cannot be seen temporarily in the AE preview