Max Xi Hero has a DisplayPort connector and HDMI connector for iGPU. Code only has HDMI.
Hero has a PS2 port on the rear panel. Code does not.
Code has an AsMedia USB3,1 Gen 1 Controller that Hero does not, so there are more USB3.1 ports on the Code. Glancing at the rear IO panel, the Hero has 2 USB3.1gen1 ports while the Code has 6. Hero has 2 USB2.0 ports on back. Code has none.

Hero
Intel® Z390 Chipset :
4 x USB 3.1 Gen 2 port(s) (4 at back panel, +red, 1 x Type-C+3 x Type-A)
Intel® Z390 Chipset :
2 x USB 3.1 Gen 1 port(s) (2 at back panel, +blue, 2 x Type-A)
Intel® Z390 Chipset :
6 x USB 2.0 port(s) (2 at back panel, +black, 4 at mid-board)
Intel® Z390 Chipset :
1 x USB 3.1 Gen 2 front panel connector port(s)

Code
Intel® Z390 Chipset :
1 x USB 3.1 Gen 2 front panel connector port(s)
Intel® Z390 Chipset :
4 x USB 3.1 Gen 2 port(s)
Intel® Z390 Chipset :
8 x USB 3.1 Gen 1 port(s)
Intel® Z390 Chipset :
4 x USB 2.0 port(s)
ASMedia® USB 3.1 Gen 1 controller :
2 x USB 3.1 Gen 1 port(s)

The PCIE lane arrangements are different.

Hero
Intel® Z390 Chipset
2 x PCIe 3.0 x16 (x16 or dual x8 or x8/x4/x4)
1 x PCIe 3.0 x16 (x4 mode) *1
3 x PCIe 3.0 x1

Code
2 x PCIe 3.0 x16 (x16, x8/x8, or x8/x4+x4)
Intel® Z390 Chipset
1 x PCIe 3.0 x16 (max at x4 mode) *
1 x PCIe 3.0 x16

I think that is everything, The VRM is identical AFAIK.

Thank you for your help ZAMMIN and BILLBITTEL@ME.COM. Things are a bit confusing because the only difference that ASUS show here:
https://rog.asus.com/articles/maximus-motherboards/introducing-rog-maximus-strix-z390-gaming-motherb...

are the PCIe lanes, Code =
3 x16
1 x1

Hero=
3 x16
3 x1

Yet the Code is some 80 bucks more expensive?

But BILLBITTEL@ME.COM you say that there are much more differences than what is shown in the above link regarding Code having the Asmedia USB3.1 controller where as the Hero does not, yet you also say Code has more USB3.1 ports due to the Asmedia controller which is missing on the Hero. The above spec show that both boards have the same number of USB ports, though?

I notice my XI Code has only one PCIe 3.0 x1 port and the hero has 3 x PCIe 3.0 x1 ports which is what was confusing me regarding why the Code costs more. But I see that the SLI capability is better with the Code, as is were. I have never used SLI so I am not well rehearsed with the Lane's featureso the differences in the lanes is a bit confusing with these 2 boards. However, I believe I can get my head around it if it were explained in a "PCIe 3.0 x 16 Maximus XI Code vs Hero for dummies". Although BILLBITTEL@ME.COM has explained it in technical specs terminology, which I am usually comfortable with. Thanks again, guys.

BTW the attraction to purchasing a high end mobo with SLI capability is that I do not mind paying more for a product that has features that I might not use but more importantly it is made using best quality electronic components with advanced engineering [although this generation of ROG Maximus XI is somewhat lacking in the VRM side, unfortunately].

Hi, this may help.

https://www.asus.com/uk/Product-Compare/?products=HoZGpSKey80hlF3B,MQ9gaOaFluarIrbV&b=2

The different in spec is PCIe_x1 slots (3 on Code, 1 on Hero) and integrated WiFi (optional on Hero).
Code apparently has more built-in fan/pump headers and temp sensors for watercoolers.
Aesthetics are different, ROG styling and AURA seem to be presented differently on the two boards.
And price is different, of course.

Full descriptions and comparisons (about everything except VRMs, lol) are here.

Sometimes a picture is easier. This is what I meant about the difference in USB ports on the XI Hero verses the Code. The Code has 6 USB3.0 ports on the back, the Hero has 2.

XI Hero Spec says
Intel® Z390 Chipset :
4 x USB 3.1 Gen 2 port(s) (4 at back panel, +red, 1 x Type-C+3 x Type-A)
Intel® Z390 Chipset :
2 x USB 3.1 Gen 1 port(s) (2 at back panel, +blue, 2 x Type-A)
Intel® Z390 Chipset :
6 x USB 2.0 port(s) (2 at back panel, +black, 4 at mid-board)
Intel® Z390 Chipset :
1 x USB 3.1 Gen 2 front panel connector port(s)

Xi Code Spec Says
Intel® Z390 Chipset :
1 x USB 3.1 Gen 2 front panel connector port(s)
Intel® Z390 Chipset :
4 x USB 3.1 Gen 2 port(s)
Intel® Z390 Chipset :
8 x USB 3.1 Gen 1 port(s)
Intel® Z390 Chipset :
4 x USB 2.0 port(s)
ASMedia® USB 3.1 Gen 1 controller :
2 x USB 3.1 Gen 1 port(s)

I did notice that on the comparison page that SilentScone posted, the USB lists are the same and they both list an Asmedia USB3.1 GEN 1 controller. They are not the same on the individual spec web pages. Maybe a typo. Also, I do not think WIFI is optional on the XI Hero like it was on the X Hero boards.