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Long gamma-ray bursts (GRBs) frequently exhibit complex prompt-emission morphology, including a bright main-emission (ME) episode followed by a weaker extended-emission (EE) component. Whether these subcomponents are produced by the same central engine under different physical conditions remains unclear. Here, we present a systematic, pulse-resolved analysis of 24 Swift Burst Alert Telescope (BAT) long-duration GRBs that exhibit a well-separated ME episode (G<SUB>1</SUB>) followed by a fainter EE episode (G<SUB>2</SUB>) after a background-consistent quiescent interval. For each episode, we measure the episode-only duration (T<SUB>90</SUB>), count-based hardness ratio, minimum variability timescale (MVT), and spectral lag using the same Swift-BAT analysis pipeline adopted in Paper I. We find that the EE is typically softer and smoother than the ME: HR<SUB>EE</SUB> &lt; HR<SUB>ME</SUB> in 20 of 24 events, and MVT<SUB>EE</SUB> &gt; MVT<SUB>ME</SUB> in 19 of 24 events. The EE also shows a broader lag distribution, including both large positive and negative lags, although the sample-wide median lag offset is not statistically significant. Both episodes remain in the long-GRB track in the duration─hardness and duration─MVT planes. These results suggest that the EE in long GRBs may represent a physically distinct regime of the central engine, characterized by a lower luminosity, longer emission timescales, and softer spectral properties, rather than a simple continuation of the main burst. The observed trends are consistent with late-time central engine activity, such as fallback accretion onto a black hole or protomagnetar spin-down.