Could Japan seize the East Indies without Pearl Harbor?

Could Japan have taken the Dutch East Indies without bombing Pearl Harbor?

No; a Southeast Asian war would still bring conflict with the United States, so Japan would seek to neutralize Pearl Harbor.

A Japanese offensive into Southeast Asia could not be isolated from American interests and military power. No plausible campaign for the Dutch East Indies avoids eventual war with the United States. If conflict is unavoidable, Japan still has a reason to try to neutralize the Pacific Fleet at Pearl Harbor. The criticism is that Japanese forces could have used their effort there more effectively.