Migrating sprites from one project to another?

There probably isn't a way to do this (except the long way), but around 4 years ago I started creating a game that's selling point was the 100's of unique playable characters a player could choose (ambitious, I know). To that end, back when all I had was Construct 2, I did the sprite work and animations for around 50 of them along with some programming. Anyway, I got the free year of Construct 3 but I still kept using the C2 project to insert all of my game assets (mostly because of C2's plugins that I'd added on).

Well, fast forward to now. C2 isn't being supported anymore, but I don't have the money at the moment to do C3, and even if I did, I really, really don't want to have to migrate all 200+ sprites from C2 to C3, but I can't just open my project in C3 because of a bunch of rexrainbow plugins that I've added. So what I need is one of two things:

1. Is there any way to copy and past completed sprites with animation parameters, names, etc. from one project to another (or runtimes)? OR

2. How do I add the rexrainbow plugins to C3 (provided you even can on the free edition)?

I'm really hoping I don't have to tediously reinvent the wheel. Thanks in advance.

If your goal is to move the sprites, just delete the plugins and open in c3.

I'm genuinely not sure how to delete the plugins... they were installed via rexrainbow's proprietary installer tool.

Deleting all your events and any behaviors, objects, or effects that are not default ones should do the trick.

Unfortunately, no dice. I have deleted all the behaviors, events, and effects that weren't the defaults and what it says is "Failed to open project. Check it is a valid Construct 2 single-file (.capx) project." I'm positive that I have saved it as a capx in Construct 2. I've double checked. I've even installed the missing plugins into C3 and it just won't import. I'm even using an older version of C3 that still uses the C2 runtime. Any other ideas or suggestions?

Looks like I'm far from the first person to experience this issue. Looks like I'm going to have to get rid of everything except the sprites themselves.