Hi everyone, an update since I can't edit my post. Here are the links people have shared in the comments here and on a separate post I made on the r/notebooks sub:

THE NEW WINNER! Definitely the closest match!! (Watercolour pattern pages - Amazon).

And two more! Journals by L'rara (imagine Japanese style paintings on the pages!).

Colourful blank dot grid journal w/ coloured pages (Blomwild.com)

C̶l̶o̶s̶e̶s̶t̶ ̶f̶i̶n̶d̶ ̶s̶o̶ ̶f̶a̶r̶:̶ Citrus book bindery does custom notebooks with coloured paper (expensive tho!)

Small Dot Grid Stamp (Etsy).

Site (for any UK users) that does custom A5 stamps.

Slim dot grid notebooks with coloured pages (Etsy).

Slim A5 Midori Dot Grid Notebooks with coloured pages (Jenni Bick).

Suggestions 4 DIY dot grid paper: - Printing dot grid onto coloured paper and binding your own notebook. Highly customisable dot grid pdf maker without a watermark. Also: Lined, grid, graph paper printables (Etsy). - More printing suggestions: printing pastel patterns/coloured paper with a colour printer and then adding dot grid. Pastel paper printables (Etsy). - Using stencils to draw a dot grid onto pages: Various bullet journal stencils (not necessarily dot patterned tho!) Dot grid Sashiko embroidery stencil (Etsy). &: Embroidery stencil no. 2 for any peeps in the UK.

Where to buy the notebooks featured in the images: 1)

2)

https://www.amazon.com/dp/B0BMBDSYRZ

What about this one it's exactly what you're talking about but you didn't include it