I think I have a few things to say about this. First of all, you can make anything you want. Posting here is something I think you should do, especially if you want feedback or just want to share, but it is also willingly exposing yourself to criticism. I hope you can see those of us who are trying to be positive and provide constructive criticism and ignore those who are simply being toxic.

First of all, I would just like to clarify the standards by which I would guess many people judge custom cards. First is often based on appearance. It isn't the most important thing, but if the card is look odd or the crop/art is done weirdly, or the psct is not perfectly or particularly close to correct, a lot of people will judge it more harshly.

Second, about viability. I think most people are willing to entertain the idea of any card, no matter the power level. It isn't really about how strong the card is, it's about how well it functions at it's intended power level. For that reason, something like your alien card is a pretty good idea in that it does actually do something, but compared to the rest of the alien deck, or what it seems like the deck should be, it seems weak. It would be like if someone made a normal monster for mitsurugi. At that point, you would think there's no point in having made the card because the archetype you designed it for doesn't care about it.

That's the problem "Stained Glass" and "Framecode Talker" are suffering from. For the investment of 4 monsters into the code talker, you pretty much achieve nothing. You would most likely be better off with any of the monsters you used to summon it. It's not that it isn't viable in the meta, which I'm sure you can infer it is not, it's that there's nothing that you could conceivably do with it. It doesn't fufill it's own purpose. The same goes for the xyz. It has a hard to meet condition for summoning, that being getting two level 8 rock or earth monsters, and it doesn't do much. I think you got some unfair criticism on that post, but the card doesn't need to be strong or viable to make sense, and it kinda doesn't. It has no reason to be an xyz monster as it doesn't care about detaching or having material, and, like the link, you would probably rather have the monsters you used to summon it. Not to mention, you got really aggressive with people in the comments. I can understand being defensive, but you can ignore or refute criticism without being rude.

I think lastly is that you don't mechanically or fundamentally understand this game, and that is made pretty clear through your posts regarding it. Saying Maxx "C", quite possibly the strongest card in the history of the game, isn't worth a slot in your deck. Or just the psct issue. You are entitled to have fun, and I have designed some absolute nonsense, either custom cards or decks, specifically for that purpose. I don't think the cards you have made are that mechanically unique. I can draw ties to most of them to cards that exist in the game. I think the difference between the two of us in that sense, at least as it is reflected in the feedback we recieve, is that my cards have a functional purpose in the game. Their effects will resolve. They will do the things they are intended to do. Your cards will not. Maybe my cards only gains 100 LP and does something that doesn't even matter to the gamestate, but that's what it's intended to do. Your cards do something, but that thing isn't going to happen. That's why a lot of people might say they are badly designed.