I have visited the Manzana Jesuítica and the crypta in Córdoba as well as the estancias Jesús María, Caroya and Alta Gracia. 
 
I have really enjoyed staying a week in Córdoba because this big student city is lively as it's full of young people, good food and it's cheap. 
 
The city center contains some highlights next to the WHS like the Cathedral and the Memorial place for the victims of the dictatorship in an old police station. The manzana jesuítica is the jesuit block in the town set-up and consists of a school, the law faculty of the university of Córdoba and the church. The university part is also a museum complex that can be nicely visited for currently 400 Pesos p.P.. We obtained a small bookled in German at the entrance and walked through the Jesuit rooms containing old books and maps. Also we asked a security guard to open the graduation hall which is the aisle of the church, but only accessible from the patio of the university. Finally we had a short look into the big and beautiful church during a mass. 
 
Additionally during two day trips we went to Alta Gracia (35 km from Córdoba) and Jesús María (50 km from Córdoba). To Alta Gracia buses run from the new terminal and take about an hour. Companies are Sierras de Calamulchita and Sarmiento and prices are around 400 ARS per ride. Only during the night there are no buses. You can check times in advance on plataforma10.com.ar and buy tickets at the driver or at the counter in the terminals. Alta Gracia has a nice town center with a lake and the estancia, which has an self- audio guide tour in english for your phone. The Wifi wasn't working so best to use mobile data. The self-guided tour is interesting and gives some insights into life on the estancia. My highlights were a German Luther bible and the accounting book of the Jesuits, that I only heard about though as the door was closed for Siesta. As others before I can highly recommand the Che Guevara museum around the corner in his youth home that I found really interesting and touching.  
 
In Jesús María there are two estancias that can be visited. Again there are two bus companies that run for 450 ARS currently from the old Terminal to the town often outside nighttime. The companies are Fono Bus and Ersa Bus and the counters to buy the tickets are downstairs in the old terminal (the one that is also for long distance buses). In Jesús María we got off the bus before the terminal next to the big unfinished highway bridge in order to walk to Caroya Estancia. There is a visitor center on the main road with information on all jesuit sites and with some general facts and baños. After reading through the signs we walked the few meters down the gravel road to visit the estancia. Before reaching the main building there are some remainings with explaination signs of the craft sites like an oven, a storage building, a mill etc.. The estancia building is well preserved and in each room there are information in chronological order in Spanish on the history of the building from Jesuit times to a visit of Belgrano in the independance wars until the Italian immigration wave during which immigrants stayed there. It's quite a lot of information and not all is interesting, but still it's worth a stop. It costs only 100 ARS currently. The woman working there was so kind to call us a taxi that brought us to the estancia Jesús María in town. There is a nice park and again some information signs in the building plus a church to visit that apparently was never finished in its interior due to the 1767 expulsion of the Jesuits. The collection of coins upstairs is nice- probably you will find some old coins from your country as well. The best part about our visit though was an art auction in the church and a free concert afterwards in the patio with indigenous sounds. Was a nice round- off of the visit.  
 
It's nice to visit Córdoba and some of it's less touristy surroundings in a few days and it gives good insights into the history of the Jesuits in this area. Also everything is much better preserved than in Missiones and Paraguay. Nevertheless I find it's more an interesting WHS not a fascinating one.