Change skins and check again
I had this on my MiniMX (S905) box but only had an issue with Aeon Nox Silvo (it had LE logos in the actual addon resources - not anymore). The default skin was OK.
Also deleteing /storage/.kodi/userdata/Database/Textures13.db will wipe out any cached images held by kodi
edit ive posted on the estuary mod thread on the kodi forums see if they can help edit
weird, it does indeed appear to be a skin issue.
on my 905 box, with 8.9.2 installed to internal the libreelec branding as the above pictures no matter if I select the default skin or estuary mod v2…
but heres where its weird, if I boot of a sd card card and run it off that and select estuary mod v2 it changes from coreelec branding to libreelec. if I change back to the default skin it goes back to coreelec branding.
so it seems to be right if booting of a sdcard and it won’t change if running from internal.
I’m using Estuary MOD V2 also. It requires some skin changes to get the CE icons to show up. I got them to show in the CE settings wizard (your first screenshot) by renaming or removing the 3 service-LibreELEC-settings*.xml files from /storage/.kodi/addons/skin.estuary.modv2/xml directory. Replacing the LE icon on the Kodi settings page (your second screenshot) is a bit more work. You have to modify the Settings.xml file and rebuild the media/Textures.xbt file with the new CE icon included.
Aeon Nox Silvo Mod skin is hard coded. I’ve been able to replace LE logos and change LibreElec to CoreElec, in settings (procedure is similar to as described by @no1home) but it remains in the settings page ‘hints’ when CoreElec is hi-lighted.
The best way is coreelec creators must use another name/id for service addon like service.coreelec.settings with renamed xml files too because ‘service-LibreELEC-Settings-mainWindow.xml’, ‘service-LibreELEC-Settings-getPasskey.xml’ and ‘service-LibreELEC-Settings-wizard.xml’ files are also used for coreelec.
I’m 99% certain I did a new install with CE when there was problems with the remotes. I can redo it with 8.9.2
Later just to be on the safe side if you want.