Unfortunately, for Minecraft Java Edition, there are no skins that will automatically incorporate a cape. However, in Bedrock Edition, there are some skin packs that come with capes included.

The Minecraft Java and Bedrock editions are no more - please welcome the Minecraft Java and Bedrock Edition, which is coming in June to fussy PC players ...

Minecraft: Java Edition is the legacy PC version of Minecraft and often gets updates at different times than other versions. The 1.16.5 update is the latest release and is currently rolling out to ...