Should a good quality French mayo be cream coloured, not white, and is hollandaise sauce, mayonnaise with lemon juice ?

All Pyrenees France from https://all-andorra.com/

Yes I believe. When I was a kid and we made some home made at home it was kind of yellow because we used egg yolks.Do not other countries use egg yolks

In France, mayonnaise is yellow because it is made with a egg yolk and too, the mustard we put inside.

About the Hollandaise sauce well, it has nothing to do with mayonnaise: no oil and no mustard inside.  And once again: it is yellow because the egg yolks. The lemon juice hardly colors it.

Although it's name doesn't say it, since ' hollandaise ' means:  Netherlands, it's a French sauce.

It was invented during the reign of Louis XIV, to finish with fatty sauces. It was created during the Dutch War (1672-1678), hence its name. 

It is used as a base for a whole category of sauces, notably Béarnaise sauce, and is used in the composition of Bénédicte eggs.

French mayo should be cream not white.

Hollandaise sauce is made with butter, lemon juice, eggs [ see Google for recipe  ].

mayo, ats its most simple is egg yolks and oil with seasonings. The egg yolk does indeed color the mayo slightly cream colored.

AND no Holandaise is not mayo with lemon juice. Most mayonaises have some lemon juice in it, just not as much as hollandaise does.  

Mayo does not have an egg yolk, Hollandaise does. Two completely different things. 

Mayo has egg yolk so the color will depend on the color of the egg yolk. That can range from pale yellow to a dark orange.

Hollandaise is different from mayo.  It is cooked, it contains other ingredients that mayo does not. BUTTER, lots of it as well as lemon juice. 

Mayo should contain egg yolk, so it should not be white. 

Hollandaise is not mayonnaise at all.  It is an emulsion of egg yolk, butter, and lemon juice but the proportions are very different.  It is easy to curdle the egg yolk as you whisk it into the hot melted butter

Mayo on the other hand often uses oil at room temperature, instead of melted butter .. so it is not going to curdle on you.