Hi,

What I can understand this is mostly an animated dashed border, marching ants border, or marching ants effect.

The "marching ants" name comes from image editing software like Photoshop, where a dashed selection outline appears to continuously move around an object.

Here's what it looks like conceptually:

+ - - - - - - - - +
|                 |
-                 -
|                 |
-                 -
|                 |
+ - - - - - - - - +

The dashes don't grow from left to right they continuously travel around the entire square.

CapCut doesn't have a built-in "marching ants" border effect. You can make it by:

1. Creating a square with a dashed stroke in another program (After Effects, Canva, SVG editor, etc.).

2. Importing it into CapCut.

3. Animating it with:

   • Stroke Offset / Trim Paths (if created in After Effects), or

   • A seamless looping video with the dashes already moving.

Here is a tutorial in CapCut about Dash or Dotted Line Animation in CapCut PC for Better Visuals

If you are using After Effects

The easiest method is:

• Draw a rectangle.

• Add a Stroke.

• Enable Dashes.

• Animate the Offset property of the stroke.

This makes the dashes appear to endlessly travel around the rectangle.

Search terms that will find the effect

Instead of searching for "dashed line animation," try:

• Marching ants border

• Animated dashed border

• Moving dashed rectangle

• Stroke dash offset animation

• Animated dashed outline

• After Effects marching ants

• SVG stroke dashoffset animation

These searches are much more likely to show the exact effect you are after.

If you only have CapCut

If you don't have After Effects, you have two practical options:

• Download a transparent "marching ants border" overlay (MOV with alpha or PNG sequence/GIF) and place it over your image.

• Create the animation in a free tool like Figma (with plugins), Blender, or an online SVG animator, then export it and bring it into CapCut.