Ugdhar

I would guess one of the mods is poorly written, and is attempting to load client classes in a server environment. Unfortunately I can't tell which one it is, so unless someone else chimes in with the answer, you'll have to remove the mods one (or a few) until you figure out which one it is.

One of the mods is trying to access client classes on the server. Unfortunately I cannot tell which one, so all I can think is to remove mods a few at a time and see if they fix the crash, when it stops crashing, one of the mods you just removed is the culprit, start adding them back 1 by 1 and wait for the crash to identify the bad one.

Please post logs as explained in the EAQ to provide more information. Also, where did you download forge and your mods from? There is no forge that is compatible for 1.12-1.14, there are separate versions for each.

If you remove Optifine from the server, will it load? I believe Optifine is not meant for servers, only clients to increase performance.

You need to reassociate .jar files with Java, I believe there is a program out there called jarfix that does just that.

You need to upload your logs to pastebin or a github gist, and then post the link here. This will provide information for people to look and hopefully see what is crashing your minecraft. Otherwise we have no way of knowing what is going on!

Remove that mod and see if it still crashes. You should fully peruse your crashlogs, there is often (not ALWAYS, but often) a plain-english explanation.

You do not have the correct version of forge specified in the installation. The installation is using 2768, and Pixelmon 7.07 wants 2838, just like it says on the front of the pixelmon website.

If you remove LargeFluidTank does it still crash?

He means the folder containing the mods, it's on your desktop, not where the mods are actually supposed to go per the installation setup.

Read the Pixelmon website, you're not using the version of forge they say to use. Always read the instructions!

Show your full log plz, upload to a GitHub gist or pastebin and post the link here

I do not believe 1.10.2 is supported any longer. That being said, looks like googly eyes is causing the problem. Try removing that and see if it helps, however, be warned future topics related to a version as old as 1.10.2 will potentially be locked by moderators.

If you are behind a firewall/router, you will likely need to forward the port to the computer running the minecraft server. Instructions for doing this vary from router to router, consult the manufacturers website or instructions for how to do it.

Make sure you only download mods from curseforge or directly from the mod authors website, do not use sites like 9minecraft. See https://stopmodreposts.org/ for more info. Any mods you might have downloaded anywhere else I would delete and redownload. (some of your mod filenames suggest you downloaded them from elsewhere)

A good rule of thumb, any website that throws a random number in front of a product name is probably shifty

What folder are you choosing as your workspace when you load into eclipse? Just curious, since I see that message about overlapping.

Not sure if it's related to your issue, but I would remove optifine from the server, since optifine is a client mod for increasing performance. After that, I see an error about bloodmagic, maybe try updating that and/or forge to the most current/recommended versions.

If you need help finding logs, the EAQ has info on finding them:

It looks like perhaps you are trying to use a 1.14.4 version of the replaymod with 1.13.2 Remove the mod, update it, or install forge for 1.14.4 and update your installation, and see if that helps.

What happens if you try more than 5 mods? Please post logs to show us what happens.

The only mod I see referenced in this log is speedy hoppers, if you remove that mod, does it still crash? also, where did you download mods from? I would only download them from Curseforge, if you downloaded them from shady websites like 9minecraft, delete them immediately and redownload them from curseforge. See https://stopmodreposts.org/ for more information on why this is bad. If you got your mods from a legit source, and it still crashes after removing speedy hoppers, post the new crash.

Make sure you read the instructions for mods you use, I'm pretty sure you're not using the correct forge version as stated on the pixelmon website.

Moderators will tell you the same thing. And if you've got the same problem, then post your screenshot of the updated launcher as DaemonUmbra asked the OP.

You should create your own topic, and post logs/screenshots so people can attempt to accurately diagnose the issue.