You’d like to commission other people to create a game for you. This is not very uncommon – many companies do this, for example, for marketing campaigns.
However, to have success running the development of a game, you will need some experience from game development, and some experience from running businesses in general. Else, there will be too many things that will come as a surprise to you, that can totally sink the project.
First, if your first concern is “getting scammed,” then you haven’t ever done business before. There are very few “scammers” in a real business – if you look at projects that the team has done before, and actually interview the team (could be on Zoom) before engaging in a contract, you’re very unlikely to get “scammed.” However, it’s totally possible that either the team isn’t as good as you would hope (game art is HARD!) or that problems in communication end up resulting in an outcome that is not what you imagined it would be in your head. (In fact, this is almost certain to happen – make your peace with this already!)
Using a local team is usually best if communication will be the main challenge. Using a remote team is better if you can get very large cost savings (e g, low-cost teams from Brazil, China, or India) but the communication overhead is a real problem – the time it takes to establish good process and communication will probably eat up a fair chunk of your initial budget, so going non-local usually only makes sense for large projects. Europe is big, though! If you’re in Norway, and the studio is in Hungary, there are a couple of time zones difference, but there’s also a language and culture difference, that might be similar to the differences you’d experience with countries further East. Trying to “enforce the law” in a different country in Europe is still very expensive – it’s much better to define a set amount of work per milestone, fund the development towards the milestone, and break off collaboration if the studio can’t meet the milestone. Yes, you will have to pay for some amount of work you don’t use, but that’s a small fraction of the total budget, and happens all the time in any kind of development contract (not just games.)
When it comes to money, expect a single character at modern quality to cost between US$50,000 and $100,000 in development. (This can easily get much more expensive if you need to develop custom character tech.) Multiply this by the number of characters and variations your game needs. Simpler characters (animals, enemies, etc) can be lower cost, if they don’t need that level of detail. Now, add a similar amount of money for each “scene” or defined location in your game. A single level may have multiple “scenes,” depending on size. Or, if you use a streaming world, you’ll need a fair number of “scenes” spread across the world to sustain exploration and interest. All this is “scenery” for your game – you haven’t gotten to the actual “gameplay” yet, which can be simple (for a run-and-gun shooter, or explore-and-find-the-buttons platformer) or quite complex (open world, simulated population, vehicles, etc.) There’s also equipment – does your game have weapons? What level of sound and visual effects do the weapons have? The cost of a “map” can vary WILDLY depending on how big and complex it is. Once you have the map working with one “season,” re-skinning it for another season will likely add maybe 25-50% extra cost per extra season, depending on complexity.
Adding multiplayer will at least double the development cost of a game, as rule of thumb.
You don’t need UE5 to get started. Any project started on UE4.26 will be convertable to UE5. You should set aside some budget for converting to newer engines, as well as for testing on each platform you’re interested in releasing on. Additionally, if you want to develop for consoles, you need to make sure the contracting house you choose already has experience with that particular console and publisher, so that the tech certification and release process can be budgeted in appropriately.
When using assets in maps, this is really up to the artists you choose to work with. Whatever tool they are most familiar with, should be what they use! Megascans are OK if you’re making things that look like their assets look, but if you want a different look, you’ll need different source materials. Compare the look of “Borderlands” with the look of “Breath of the Wild” with the look of “Call of Duty” – different art styles require different sources.
You don’t particularly need to “look up” a name for a game, as long as it’s not trademarked by someone else. If Google finds nothing, you’re probably doing OK. A trademark attorney can do a full search to both make sure that it’s not taken, and help you file an application for trademark in each jurisdiction you’re interested in protecting.
So, in brief: If you have a few million dollars, and experience in running contract projects from any industry, you may be able to achieve the game you want through contracting with a third party studio. The main challenges are going to be around finding a studio whose skills, style, and experience matches your expectations, and then structuring the work in a way that reduces risk and increases clarity of communication on both sides. It would make a lot of sense to spend a significant amount of the budget (15-20%?) on pre-production, such as putting together concept art, story boards, examples of the level of detail and look you want, planned-out plots of maps and situations, etc, because you don’t currently have any development experience. Again, there are studios (or just people) who have this experience, who you can contract or hire to help you with this.