Did you add all of the various language EULAs to the appropriate language-specific nodes in the Support Files view of your Suite/Advanced UI project?
The following help topic explains how the installation determines which language to use when displaying the wizard interface text (and the EULA, assuming that you have added all of the EULAs the appropriate nodes in the Support File view): How InstallShield Determines Which Language the Installation Runs In
As per my understanding, If I add EULA in support files. It will show that according to the installer's language. But we have to show EULA based on System Locale (irrespective of Installer's language) Is there a way to do this.
That sounds like an unusual use case. There is nothing built in to do that, but you could perhaps wire something up to do this by using your own custom extension DLL.
To start, you'll probably want to hide the InstallationLanguage wizard page. (To do so, in the Releases view, select the release that you are building, and on the Build tab, find the Languages Dialog setting, and set it to No.)
In the Support Files view, you would add each of the EULA files. Then you'd write an extension DLL that would determine the system language of the target system and select the appropriate EULA file. For your wizard page UI, the Next button of the wizard page directly before the EULA wizard page would call your custom DLL. When the end user clicks the Next button, your DLL would determine the appropriate language and then display the EULA wizard page with the appropriate language text.
