When comparing jMonkey3 vs Stride, the Slant community recommends Stride for most people. In the question“What are the best 3D game engines?” Stride is ranked 5th while jMonkey3 is ranked 12th. The most important reason people chose Stride is:
Looking nearly as good as Unreal Engine 4, but rendering significantly faster.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Java is a great development platform
Java is a well-optimized just-in-time compiled language. It's faster than languages without an effective native-code compiler such as Python or Ruby, similar in speed to other just-in-time compiled languages such as C#, while slightly slower than compiled languages such as C or C++ (with some low-level and numeric benchmarks being similar to C++).
Java also has a wide variety of high-class IDEs available.
Pro Multiplatform support
Code can be ported to mobile (iOS is in the works) and other Android supported devices with minor changes to the code (just change some implementations that vary on the platform such as inputs and user interface). It can even run on certain Raspberry Pi devices.
Pro Free and open-source
jMonkey is completely free, meaning it's possible to develop and release a game with no fees or royalties. Because it is open-source, jMonkey has plenty of people fixing bugs and, adding to the engine as well as creating a variety of plugins that can be used in the engine.
Pro Not limited to using its own IDE
Unlike some engines, jMonkey doesn't force its own IDE. You can use its Netbeans-based IDE, but you can also set up a project to work in another IDE such as Eclipse. You can still use the special tools from jMonkey's IDE in such projects.
Pro Engine modifications can be made using Java
Because jMonkey is implemented in Java, the same language its apps are typically developed in, developers will have an easier time modifying the engine to their needs.
Pro Has everything
jMonkey3 handles input from computers and mobile devices. It handles networking, physics, rendering, terrain, and cinematics.

Pro Ease of extensibility
Engine is modifiable.
Pro Freedom of choice for architecture
The user is not compelled to use any programming architecture nor standard in order to make a project working. JME allows the freedom to use what is best for a game.

Pro Offers both low-level and high-level ways of editing shaders
Modifying shaders can be done either via a visual tool called Shader Nodes or via GLSL that allow you to make your own shaders without the engine getting in the way or having to hack around to do so.

Pro Good looking and fast
Looking nearly as good as Unreal Engine 4, but rendering significantly faster.
Pro No royalties or licensing fees
Pro Projects are normal Visual Studio solutions
No proprietary project format, so it works with all the official .NET tooling.
Pro Supports Visual Studio
Pro Very modern render engine
Pro Powerful 3D Rendering Engine
Supports Vulkan. You can achieve good quality as in Unity3d and Unreal Engine

Pro Straightforward editor
Stride provides a simple and clean working environment for designing games.
Pro Community seems friendly and is growing
Pro Engine AND Scripting are both C#
Since the engine is written in the same language as the scripting, there is no weird mix of technologies as other engines have.
Pro Supports Vulkan
Currently the only well known open-source game engine that supports Vulkan, and probably one of the only.
Pro Easy to learn and use C#
Pro Multiple Starter Templates
The engine comes packed with multiole example projects to help you get started.
Cons
Con Terrible API reference
The methods are not defined.
Con Not an engine for total beginners
While it's clear that you need to know Java first before using this engine, it is recommended that you have some programming experience as well. Most performance issues and memory leaks are more due to bad programming practices than the engine itself.
Con Slow release cycle
jMonkey3 lacks manpower to have a fast and decent release cycle.
Con Relies on archaic tool chain
jMonkey Engine uses Apache Ant for build automation, which is archaic and backwards, even by Java standards.
Con No terrain editor
Unless you like working on planes, there is no terrain support.
Con Editor is Windows only
Since version 1.7, Linux can be targeted for runtime. The editor for the engine is available only to Windows though.
Con Small user community
Unity and UE have a vast amount of user community.
Con Does not currently support Playstation or Switch games
Con Iteration may be slower than with other engines due to longer "build" times when certain changes are made
Con Shader system require's overhaul
Shader's are not easy to get to grips with and Stride's shader system. Needs overhauling for easier use.
