what would you recommend to web scrap for batches of Base58 (legacy) addresses? what is the best way to find loads of them and inquire into their TXs and balance?
Blockchair.com has data dumps.
https://gz.blockchair.com/bitcoin/addresses/The file for Bitcoin addresses on 22-May-2024 01:23 is 1 GB. You can download the file (.tsv) and do your filter to check Legacy addresses and balances.