[Baertram]

JoviexsAddonSettingsTransferUpdated is not working anymore?
For no addons or only some?

Most addons are not using the "character names" anymore (which is good as the settings will be usable even after a character name change now) in the settings file so you need to check for the unique character IDs! The last known character name of the characterId is shown in the table's sub-entry ["$LastCharacterName"] then!

Hope the following helps:

These different SavedVariables structures exist:

Server independent, Account dependent settings

AddonSavedVars =
{
    ["Default"] =
    {
        ["@AccountName"] =
        {
            ["$AccountWide"] =
            {
            },
        },
    },
}

Server dependent, Account dependent settings

AddonSavedVars =
{
    ["NA MegaServer"] =
    {
        ["@AccountName"] =
        {
            ["$AccountWide"] =
            {
            },
        },
    },
}

Server dependent, Account independent settings (all accounts are the same)

AddonSavedVars =
{
    ["NA MegaServer"] =
    {
        ["AllAccounts or any other "no-account name" variable like "AllTheSame" etc.] =
        {
            ["$AccountWide"] =
            {
            },
        },
    },
}

Server independent, character ID dependent settings

AddonSavedVars =
{
    ["Default"] =
    {
        ["@AccountName"] =
        {
            ["1234567890123456"] =
            {
                 ["$LastCharacterName"] = "The last known name of this character with the uniqueId 12345678901234567890"
            },
        },
    },
}

Server dependent, character ID dependent settings

AddonSavedVars =
{
    ["NA MegaServer"] =
    {
        ["@AccountName"] =
        {
            ["1234567890123456"] =
            {
                 ["$LastCharacterName"] = "The last known name of this character with the uniqueId 12345678901234567890"
            },
        },
    },
}

OLD/OBSOLETE/Should not be used anymore but many addons still do:
Server independent, character NAME dependent settings

AddonSavedVars =
{
    ["Default"] =
    {
        ["@AccountName"] =
        {
            ["Your characters name"] =
            {
            },
        },
    },
}

Server dependent, character NAME dependent settings

AddonSavedVars =
{
    ["NA MegaServer"] =
    {
        ["@AccountName"] =
        {
            ["Your characters name"] =
            {
            },
        },
    },
}