You can upload a spherical map (.hdr, .png, .jpg) and convert it to cubemap.
I’ve made it possible to create 3 cubemap layouts :
The ressolution option is meant for a single piece so if You set it to 512 you’ll get 2048x1536 cross cubemap
Cubemaps are generated based on camera rotation (cubemap view)
Github repository: https://github.com/matheowis/HDRI-to-CubeMap
Online converter: https://matheowis.github.io/HDRI-to-CubeMap/