In bakin you have complete layout freedom for menus, battle menus, screens, etc.. you can use the layout tool to move all elements used in battles around to locations wherever you want them. So yes, it's absolutely possible to replicate that picture you provided within Bakin.

From what I know so far, adjusting the layout on screen is not enough to create a functional 2D battle system in Bakin. The default battle system uses 3D assets and I don't know how to make the game use 2D enemy sprites instead of 3D enemies. What's the solution?

I personally haven't tried a 2D battle system but have seen pictures of people doing it so it IS possible, you just have to try it and mess about with the layout/camera tools and make it to how you want it to be, its just not a simple case of load the engine and there it all is ready for you and you don't need to learn how to do anything. To be fair.. IF you want to make a 2D rpg maybe other engines might be a better option for you, that said...
2D sprites import into bakin just the same as 3D object do. As far as having 2d background pictures.. you can simply drop a background picture onto the editor and it will turn it into a 3D stamp object itself.. you then just place that onto the map as a background, make the camera face onto it, then just the case of camera rotation to face on, and import 2D assets. I really cant go into it that deep and give you a step by step guide 'cos ive not actually done it myself.
Your best bet is to head to the official Bakin Discord and start asking there.

Just to add to this observation of yours...
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"The default battle system uses 3D assets and I don't know how to make the game use 2D enemy sprites instead of 3D enemies. What's the solution?"
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Nope, kinda not true.. the bakin engine is more tailored to make games like Octopath Traveller.. 3D backgrounds with 2D characters.. even the game's demo game 'Orb Stories' is made this way. In the editor you have 2 folders.. 3D and 2D.. all the 2D assets are there for use and same with 3D. When you start a new project most of the assets for the world ARE 3D including battles BUT the assets the engine gives you to work with for character models are mostly 2D unless you add all the DLC packs and the SGB dlc.. then you have 3D characters available.
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It's better that you think of Bakin engine as an Octopth Traveller clone maker.. but with exxtra features that can make modern 3D and 2D platformer games, early stages of action rpgs, with also the capability for advanced scripting using C#.
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So the trick for what YOU are wanting to do is 'use and learn' you really need to custom the engine yourself to make what you want by manipulating the engine's systems. It's entirely possible to do what you want to do.. but as I said in previous post.. maybe a different rpg game making engine specifically tailored for 2D visual is your better option.. maybe one day the devs will add in a 2D battle system like SGB's or someone will make a plug-in for it at some point.

Thanks for your opinion, appreciated.
I've already asked the same thing on Bakin's official Discord some time ago and nothing helpful came out of it. So now I'm asking here, hopefully devs can make their own comment regarding 2D battle feature. It's present in their previous game engine SGB, and a 2D battle screen is present in one of the early promotional videos of Bakin engine.

It'll be great to hear a comment from the dev team.

Originally posted by MassMan:

Thanks for your opinion, appreciated.
I've already asked the same thing on Bakin's official Discord some time ago and nothing helpful came out of it. So now I'm asking here, hopefully devs can make their own comment regarding 2D battle feature. It's present in their previous game engine SGB, and a 2D battle screen is present in one of the early promotional videos of Bakin engine.

It'll be great to hear a comment from the dev team.

Well if they dont answer maybe you should @Sana on the discord group and ask her.. considering she/he works for SmileBoom and is the mediator between the community and the devs.

Up, hope to hear from engine devs.