I think your process would result in a deck that is much too large and rather ugly (bad lighting, noisy camera, cards out of focus, rotated cards &c. &c.)
What i'd do depends on what the cards look like. For hand written
cards, i'd type them in as new cards. Some work, but you can do it over
time, at the rate you learn new cards.¹
If the cards are printed (or contain hand-drawn images), if possible, i’d use a scanner rather than the phone camera.
And i recommend doing some processing of the images, from the scanner or from a camera. My personal favorite for that is
ScanTailor.
When
the cards are just printed text i'd do OCR on them, save as CSV (using
LibreOffice Calc or similar) and import into Anki. Again more work, but
the finished deck would be much nicer. Or just type the text in. Again,
you should have some time to do it.
¹That cards you add to Anki/AnkiDroid, by whatever means, are treated as new cards even if they are in a "review seldom" box for a physical card collection was a much bigger problem for me then retyping the cards when i made the switch from paper to Anki.