The Sonos Sub is designed to do the complementing you are looking for, the Sonos 5 is not.

I don't want to spend so much on the sonos sub and I thought the sonos five would work.

Do you think it is wrong? 2 We are one and a five?

Your room would then have a stereo pair of speakers plus a third sound source which will muddy the directionality of the stereo pair. Whilst the Five might produce slightly deeper bass it will also be producing all the midrange and treble sound too. The bass is what you need to enhance the Ones. Some posts on here have praised the addition of the sub to a pair of Fives/Play:5’s 

the best would be 2 five and a sub but I think it is a lot for the space I have, it is a space of no more than 40mts² so consider having two sonos one since they are discreet and work very well in stereo, apparently one day they will end with my sonos Arc in the room haha

My point was that the sub can even improve the sound of a pair of Fives, not that you should change to Fives. But still I maintain that adding a Five to a stereo pair of Ones will not give you the result you seek: you need the Sub. If Sonos offers you a money-back trial in your region buy the Five and try it, and let us know the result.