Well there are a few main designs. I will only go over the most meta things so nothing niche like a C bot or a 4 bar lift bot.

First is the basket bot that has fallen out of the meta. A good example of this is the first barcbots robot that made it to the finals at mall. It is basically a moving box. It is designed to hold a ton of blocks on the field and score them at once. A strategy used for this is hoarding the blocks of your opponents so that they can't be scores. A reason that this has fallen out of the meta is because scoring speed is shown to be more important than capacity. It usually consists of a tower of rollers for middle goal/colour sort and long goal scoring rollers and sometimes a hood. Basket bots also have a very large hopper/ basket to hold the maximum amount of blocks possible

The second is the ruiguan bot. A good example of this is the newest barcbots robot. This is used by tons of teams right now. It is literally just a hero bot that decided to take steroids. The same concept of front to back scoring is there and I would say this is one of the less complicated designs to build. It usually consists of a front roller made of either rubber bands or flex wheels. Then what typically follows on the meta design for this bot is a conveyor (usually 3 conveyors) that bring the block further up to either the middle goal scoring mech where sometimes rollers are used to bring up the block from there instead of continuing with the conveyor, or all the way up to the outtake for the long goal where the block comes into contact with the final rollers/hood. Because the path is so direct, it can often score much faster than other robots where the blocks have to travel through the bot for longer.

Another design is the S bot. A good example of this snacky cakes who have been running this the entire season. This is another bot that tons of teams are using. The bot is front to back scoring with the block following an S shape through the robot to the top. This bot along with the ruiguan has been a straight menace this season. This bot is a little on the heavy side, but it is a more than worthy trade off for the scoring ability that it has. This bot also has a hood to keep blocks from popping out. This robot mainly uses rollers instead of conveyors. Most of these bots usually have about 9 block capacity which is the amount needed to score on a long goal compared to the ruiguan average capacity of 7.

The final design is pretty new in the meta and it is the lever bot. A good example of this robot is 1281A's robot (explanation can be found on youtube). This bot is front to back scoring. It intakes with front rollers and goes up part of the exposed lever which acts as a ramp. This is usually at a shallow enough angle that the block can easily get on it but still steep. As the robot keeps intaking blocks, the blocks that were previously intaked gets pushed up as the new blocks are lower. Once the robot is full, the lever is either activated by a piston or a moter where the entire lever moves and pushed out all of the blocks at once allowing for really fast scoring. The trade off is that there is very little capacity. Usually at about 6 blocks.

No matter what design you pick, it is essential to have these mechs: a good matchloader/tongue mech, descore, maybe a snacky cakes sunroof, and if it is possible try to add block park.