Why isometric animation
The letters move along the isometric path. That's the hardest direction to animate in. Once you can do it, animating in any other perspective is easy.
Set up guides
Before you start, make a layer for guides. In a color that stands out against the banner, draw an isometric line along the top of the letters and one along the bottom, plus two vertical lines where the letters leave and enter the banner. They keep you on the path. Always keep the letters right against the guides, with no pixel gap in between.
One step per frame
Add a frame, copy everything from the previous one, and move the letters to the left. Always a whole step: one full step of the isometric pattern, never half of one. Then the next frame, and the next.
When the first letter reaches the edge of the banner, copy the sign and place the copy coming in from the right. Letters leave on the left and come back on the right. Then cut off every part of a letter that's outside the banner. That's the frame by frame part: repetitive, but worth it. Now and then, go back a frame and compare.
In the trainer the letters sit on their own layer above the banner, like in Aseprite. Move (V) drags them by whole pixels: one isometric step here is 2 pixels left and 1 up. Select (M) frames a part if you only want to move some letters, and Delete clears what you selected.
Add the blink
Once the sign is back where it started, make it blink: a couple of frames without the sign, a couple with it, three times. If it blinks too fast, add frames or make them longer. Then copy a few more frames with the sign at the end so it stays for a moment before it moves on. Mine ends up with 40 frames in total.