I believe the answer is that a woman can not be a feminist that adds anything meaningful to women's liberation and still support trans ideology e.g. that males/men can become females/women in any shape, form or way. Such a woman would be a feminist in name only. The same as a woman who supports the sexual objectification of women through porn and prostitution would. Supporting things that harm females is not feminist, regardless of the reasons for doing so.
Trans ideology maintains that gender is a spectrum with masculinity and males/men at one end and femininity and females/women at the other. That everyone falls somewhere on this spectrum just by nature and personal preferences. That psychologically, spiritually, etc., a person can be partly or wholly the opposite sex depending where they fall on this spectrum.
Feminism on the other hand, since its conception, has acknowledged that men have two uses for women; as sexual objects they can use to gain pleasure from, and as mothers to their male heirs. That men have invented a way to insure that women perform these two roles by socialising girls into them. That the reason males imposed this socialisation onto females is because if there was not this social pressure on girls to conform most would not, as it is not in our interests to do so. Because conforming to it ensures male supremacy continues.
Feminists also realise that males invented religion to legitimise their insistence that women were created to serve men in these roles. Similarly, we also realise that men have invented pseudo science like 'brain sex', that our hormones cause us to perform the women's sex role etc., to prove that women are created to serve them in this way. Moreover, since trans ideology rejects that a role is forced onto females in order to keep us serving males. And instead maintains sex roles (gender) are innate and innocuous, a male who likes hobbies and clothes that are considered part of the females sex role is considered just as oppressed as a woman who conforms. In fact he is more oppressed, as he is 'born in the wrong body' and deserves women's sympathy. As women are not oppressed and considered inferior to men because we are born female, instead we are just devalued for having an innate desire to perform a submissive role.
Feminists explain that we if refuse to conform to the female sex role we are devalued even more by patriarchy, not less. e.g. if we refuse beauty rituals etc. Unlike males, who could conform to the male sex role and assume his place on top of the social hierarchy. We never have the option of being on top of the hierarchy, whether we conform or not. Those that believe in trans ideology claim if we don't like the female role and our inferior social status we must be trans ourselves and should transition.
For these reasons (and many more) trans ideology is directly opposed to feminism. I don't see the point in arguing about 'real trans' etc., like some do, the whole ideology is misogynistic and homophobic at the foundation level.