What are your favorite multiclass combos?

I have two that I think work pretty well!

-The Wingback: Wide Mid/Wide Defender

I vastly prefer wing defenders with slide tackle to any other skill. And once I have a WD with slide tackle, making such a player into a wing midfielder too makes a lot of sense. Such a player usually already has decent to good CTR, so they're useful for holdup play in lower divisions. There are corner cases where the WD's ability to hamper special abilities is useful when placed in the midfield, and once in a blue moon, in a forward position. And more importantly, unless your wide defender is specifically trying to counter a skill, a wide midfielder with emphasis on DEF is actually the better choice for occupying wide defense positions. That fourth tile of movement lets them give slide tackle coverage from touchline to touchline while still occupying a defensive position most of the time. And even though your pass and accuracy are unlikely to be high, there will be many situations where you can turn defense into offense by move-slide tackle-move-cross (if a Head Play attacker is in position) or power shot (if you've got a clear look at goal).

-The Sniper: Attacking Mid/Left Forward/Right Forward

While the most conventional build for an attacking mid is a high PAS creator, they actually benefit more than any other class from a high ACC, thanks to their bonus to long-range shots. In order to make that work, though, you usually will have to play them 'out of position' and dump your PAS to pump your ACC. Specifically, they will start most games at either the RF or LF position. This lets them make very good use of cannon shot (for sure the best skill for this multiclass to choose), and also very good use of False Kick. Starting from the LF/RF position, the Sniper can false kick out DFs in the very middle of the central defense, then move up and towards the out of bounds line for a clear(er) shot. From the same tile, the AM can false kick out a sweeper, usually leaving teams with a sweeper completely exposed. If the keeper has better DEF than your Sniper's ACC, this is a great way to generate corner kicks on demand. If you're on roughly equal footing, slam that precise shot button and watch the goals fall.

One reason this is sneaky good is that it requires very little setup, and very often not even a successful skill check to go from possession at your backline to a goal in one turn. Paired with a midfielder with Layoff Pass, the Sniper is in position with a single action. No need for a wide midfielder to move to an advantageous crossing position or for getting your MF or FW behind enemy lines in anticipation of a Long Pass. In terms of action economy, in the right situations, having a Sniper is like having a fourth action, as useful as the long pass or layoff pass (This is also why Cannon Shot is so good).

Playing this way will get you a lot of LF and RF experience. Most of the time, this means you're taking whatever non-multiclass skill is available - level 2 on your cannon shot or the 2 stat points skill in the determination tree are good ones - but also consider taking the RF or LF multiclass, which will allow your Sniper to reach the 15 difficulty cross tile to make him a decent crosser in a pinch.

The Sniper is good enough that I don't let myself play with them anymore. They make the game too easy.