Hi. Sorry, saw this a little late.
I have only fished in the UK, although I know some who fish the Continent as well.
As a general rule, public fishing as we know it is rare to almost non-existent in many parts of Europe. DIY fishing is difficult until you really know an area and understand the system of water rights in that area and how/where to obtain permits.
IMO for the visiting angler, hiring a guide is almost a practical necessity.
It depends on what you’re into as far as fishing. Yes, there is a lot of fly fishing and the 2 main “target species groups” are trout/salmon (and grayling), and then the coarse species, carp, etc.
The thing you’re going to be up against on October 1 the trout/salmon season will close in quite a few countries or provinces. Of course, this is highly variable, so this isn’t saying you cannot fish, but that will be something to consider in the UK, Ireland, and I believe Italy.
It’s a shame you aren’t going in September, there would be time to catch the tail end of Scotland’s salmon season (Atlantic salmon, of course). Fishing Salmon in Scotland is, IMO, the baseball equivalent of getting to bat in Yankee Stadium. Everything is there, the history, the tradition, and IF it’s your day, you will have done somthing that even serious salmon anglers can wait years to do–land the King of the Gamefish.
In England, the Grayling season is open on many rivers. This can give you the opportunity to fish water that would not be available during the trout season.
You might look into Norway to see if the season is still open up there if interested in Salom.
If trout is your game, I’d look at Slovakia, the CR, and Poland to see if there is still an open season.
There is a very serious coarse fishing scene in Belgium, the NL, Poland, and in most of Europe. I don’t know much about how a visiting angler would do this. Just be are that it is serious beyond belief and the techniques and equipment used are specialized in the extreme because the fish are highly pressured and because of C&R rules, many have been caught several times.
Personally, if I were in Belgium and at a loose end for a few days in October, I’d be headed to Poland, Hungary, or Romania for some driven boar hunting, but that’s another story entirely.
Grouse