2 player adventure

[Spacehamster]

So going to quickly craft a one shot adventure for two people, they
will be having high stats and a free feat for some added power,
pc level is 6, adventure will probably just be a dungeon or smthn such
but were wondering what type of/how many monsters I should throw at
them, never done any DMing with less than 4 ppl.

Is it better with smaller numbers of monsters due to action economy?
Like 1-2 stronger monsters instead of a bunch of smaller weaker ones?
Players are eldritch knight tanky type sword and board and
a 1 fighter 5 revised beast master crossbow expert with hand crossbows.

[Mandragola]

It shouldn't be all that different. Just scale the encounters for suitable amounts of xp for two people. Make a mixture of different encounters for them.

I don't see any reason to buff their stats or give our free feats, but you can do that if you like.

[The_Hansard]

I recently adapted a pre-made one shot that was designed for a party of four that ere level 4-5 into a solo game. I had the PC start at lvl 7. I also gave him a lvl 2 npc bard who could heal and provide arcana and other useful checks and exposition. The last thing that I did was to remove about 1/3 of the monsters in each fight.

Even doing all of this I still almost managed to kill him so be careful and be prepared to alter the combat during the game (I.e. Enemies retreating at low health or when their numbers get thinned out).

[Wrakur]

An easy fix would also be having a NPC character accompany them if they're cool with that (either in the control of the players or the DM).