Cash advance and balance transfer paper checks

Every few months, I get these cash advance checks from Barclays that have a 4% fee. Back in the day, these were at a 1% fee and I used them quite nicely as an arbitrage. I’m looking to do that again. I noticed that my Chase and Citi accounts do digital balance transfers which are cumbersome and not really ideal for this “poor man’s” line of credit. Which credit card banks still do the old paper check balance transfers that can be used as a pseudo line of credit?