Okay, with 256KB of flash memory that part wouldn’t be a problem. 8KB of SRAM is still a tight squeeze but let’s see what we can do.
You’re going to want to start by disabling most of the features in lv_conf.h so that the library is as small as possible to start with. In particular you need to reduce this value. I would recommend starting with 2KB and increasing it as you need.
See after that if the IDE is still complaining.