Here's a full preview of the armor and weapons in the Imperial Champion Outfit Style that was datamined with Update 6.3.0 (Flames of Ambition DLC) on PTS.
This style should be released in April or May during the 2021 Anniversary Jubilee event.
Style pages for weapons will be available for purchase from the Impresario in bound form and will also have a chance to drop from Anniversary Jubilee Gift Boxes, while armor will probably be sold separately in the Crown Store at around the same time.
Interestingly, this style is called "Imperial Dragon" internally in the game files but it was renamed probably to avoid confusion with or unintended reference to the Imperial Dragon Armor set from The Elder Scrolls IV: Oblivion, which looks very different from the armor in this style.
If you want to discuss this datamine with other ESO players, you can join the ESO Model Viewer Discord server.
Keep in mind that these models were found in the game files and this Style is not officially confirmed. As such, it might change significantly on release or might never be released at all.