You know, by 'most' measures the plants you have should be fairly easy to keep. I get it, it's frustrating to hear that and then realize you're struggling with it, but on the bright side, it means there probably is something simple that we're not seeing.
Let's get back to basics. Here's a good reference read to get an understanding of how plants behave: Darkblade's Primer to Planted Tanks
. The guide is old, so ignore the part about watts per gallon (WPG) on lighting requirements. The main take away is that your plants need CO2, nutrients, light. I personally tend to think in that order based on my long years of struggle with algae.
You've mentioned that you use easy green, and upon my initial glance, it does seem to be an all in one fertilizer with both the macro nutrients of N,P,K and a bunch of micros. IS this the one? https://www.aquariumcoop.com/product...nt=34010876040
. You mentioned that you have a nicrew light. Whilst probably not strong, it should be enough to at least grow anubias. May even be too strong. These low light plants need way less than we think. This leaves one glaring omission. Either you forgot to mention or you don't have it. A source of CO2.
Are you dosing anything like Flourish Excel or some variant of glutaraldehyde? The other question I have is what kind of filter are you running in this tank? Fish waste buildup at the bottom suggests to me that you may have bad circulation. In tanks where people do not add any source of CO2, I suspect it at least needs good circulation and good surface agitation to get some of that atmospheric CO2 into the water and thus, to the plants. Without that, your plants are essentially, umm, drowning? for lack of better words. I've drowned plants by just leaving them in a bucket before. They just melted away. Even if you dosed, it's still necessary to have decent circulation to get everything mixed thoroughly and to get whatever you're dosing delivered evenly to all the plants in the tank, so don't underestimate the need for water movement -- whether through a filter, a circulator, hand...
(but you're not going to stand there for hours, are you?)
Some other thoughts to debunk possibly old ideas that may be in your head...
too much water changes probably doesn't apply too much to plants other than that you may have washed away the fertilizers you put in. So don't worry about the 75% from the standpoint of plants. It's a fauna thing. If your fauna can handle it, then it's not a big mistake.
nitrites are fixed to nitrates by the proper bacteria in the nitrogen cycle -- which interestingly enough, need a little bit of oxygen --- which gets into the tank via good surface agitation and circulation! So you see, not having good water movement hinders a lot of things. nitrites may not be so good for fauna, but shouldn't be a big deal for plants. At the same time, if you have dead or decaying leaves, it may be causing these levels to spike so trim off the bad leaves and take it out of the tank.
that peroxide bath for your anubias? what's a little while? Undiluted peroxide + too much contact time may be too much for the plant to handle. peroxide kills organic stuff. That's why it's working for the algae. too much and it'll start killing plant tissue
finally, too much light is also a possibility. As you have aptly discovered, reducing the photoperiod helped your algae situation immensely. Dare to reduce it further. Like @paulbert
mentioned, it'll slow your issues down. Having a lot of light forces your plants to grow faster, all the while consuming more co2 and nutrients to grow. If you lack either, then they sort of fizzle out, crash, and burn -- er melt maybe.
So yea, anyway, to reiterate. good flow, good co2, good nutrients, some light. Whatever you do, remember thats what you're trying to achieve.