Something like ifdefs are not possible within an ini file.
But why reinventing the wheel and not simply using 2 environments?
[env]
platform = espressif32
board = esp32dev
framework = arduino
monitor_speed = 115200
monitor_port = COM11
[env:OTA]
upload_port = 199.xxx.xx.x
upload_protocol = espota
[env:USB]
upload_port = COM11
upload_speed=921600