I don’t think so, as like you wrote TTN allows you to set your own. TTN also allows for adding multiple AppEUIs to a single application in TTN Console; see Registration of node with pre-configured LoRaWAN keys - #2 by arjanvanb.
That thing is already hex, as the prefix 0x indicates that what you see is a hexadecimal presentation of each byte. So, 0x8E, 0x62, 0x9C, 0x1E,... can probably be written as 0x8E629C1E... and entered in TTN Console without the 0x prefix. One caveat: when handling separate bytes, you need to know if it’s LSB-first or MSB-first, whereas 0x8E629C1E... is really just a human-readable number for which LSB and MSB do not really apply.
(When using myVariable[16] = {0x8E, 0x62, 0x9C, 0x1E,..., } in computer code, you force the computer to use that specific order; when using myVariable = 0x8E629C1E... you’re letting the compiler decide whether to use LSB or MSB when storing that human-readable value, if it provides a type that can handle such long values to start with.)