I can confirm in the Adobe Mobile Analytics 4.x SDK there is no longer support for explicit setting of variables and you must use context variables. A detailed overview on the topic and how to set events with context data is linked below:
Thanks Brain. Yes after some browsing able to figured it out. In 3.x series, version 3.3.0 got 64 bit support. Can you please help me out, How to get version 3.3.0. There is an unofficial git upto 3.1.16. and Cocoapods for 4.x.