I said few times on this TC forum, but maybe I must repeat it again:
- ESP partition is for any UEFI (be it UEFI32 or UEFI64).
- ESP partition can be on a MBR or on GPT disk.
- ESP maximum size can be as all HDD/SDD - but not very useful.
- ESP partition can be at any position on HDD, be it first, last, the 69-th, whatever.
- There can be multiple ESP partition on the same HDD !! I have 4 ESP on my HDD
- ESP minimum size can be less than 500 KB; JUST to contain the boot-loader (mini-grub preferably) and (optionally) its (few bytes) configuration. Then you can chain-load whatever kernel/loader.
- ESP format(FAT12/16/32) does not matter, as long as the firmware knows it. [Some UEFI firmware natively understand NTFS or exFAT file-systems for ESP].
But for novice users, and greater compatibility to many devices/laptops, you can use GPT type USB/disk, FAT32 format, ESP is 1-st partition on disk, etc. If ESP already exist on disk (because Micro$oft win10) use it as it is.
Oh, and full-grub (modules embedded) can be less than 1MB. The fonts do not need to be 2.5 MB, you can use an ASCII font of few KB, etc. I do not waste time admiring grub screen styles/photos, my grub purpose is to fast load the desired kernel.
PS: I like to share info/knowledge; but usually I test it (real/ virtual) before spreading other's (not-tested) info.