Fate GO doesn't appear to have an EU release, no. From what I can personally gather, it seems that the way to get it if one's interested is via third party app stores -
although that can be a hassle in itself, so it's wise to be careful there.
As for why it isn't released... while there are no unified EU gambling laws, there's been movement to impose stricter laws there after the Battlefront II fiasco. The Netherlands and Belgium were especially active on this front, with both parliaments passing laws that classified lootboxes as gambling and thus restricted or even forbade paying real money for lootboxes. Nintendo closed down Pocket Camp and FE Heroes in Belgium as a result.
Even EA eventually complied with the Belgian Commission.
And the EU published a report in July, saying that lootboxes
should be considered a consumer protection issue - they straight up mentioned NBA 2K20's trailer as an example of a game with casino-like elements:
Even if the EU (or other governments like France's and Germany's) don't neccessarily see lootboxes as gambling, they still generally see the matter as worth investigating further. Couple that with the EU report, and the Games Industry quote is apt IMO: "
The jury may still be out on the extent and nature of harm these strategies cause, but there is blood in the water and the regulators are circling. "
It's saying something when the UK's House of Lords - despite current events - also launched a similar investigation,
concluding that: "Ministers should make regulations under section 6(6) of the Gambling Act 2005 specifying that loot boxes and any other similar games are games of chance, without waiting for the Government’s wider review of the Gambling Act."
So yeah, that's a major reason why many gacha games don't release here. The EU and related governments take a much harsher stance on lootboxes (and IMHO, there is a valid argument to be made, especially considering FIFA) and gacha would likely fall under similar problems.